Unit VIII Course ProjectUniversity Case StudyCongratulatio.docx
FNS20120601
1. F rensicM A G A Z I N E
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Trace Evidence
Optimal Temperatures for
Latent Print Recovery
Evidence Photography
Touch DNA Analysis
Fingerprint Patterns
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8. Forensic science is at a cross-
roads.TheNationalAcademy
of Sciences (NAS) Report
“Strengthening Forensic
Science in the United States;
A Path Forward” has caused
the profession in the United States to question its direction. The debate, started in 2009, has yet to be resolved. The
demise of the Forensic Science Service in the UK and the development of other providers has prompted heated debate
in the UK and elsewhere concerning whether forensic science should be publicly and/or privately funded as a service
to the criminal justice system. The growth of the European Network of Forensic Sciences in Europe highlights the dif-
ferences between those well-established laboratories and those fledgling institutions setting out on the journey in sup-
port of the legal process. What should be clear to all is that scientific excellence is the cornerstone of support for any
justice system, and that academic and training provision is required from pre-university, through degree and on to doc-
toral level and onward as continuing education.
In order that research be carried out in forensic science, it is essential that there is research degree provision for the
profession. However, for those who wish to develop within their practice, particularly up to and including doctoral level,
there is currently little or no provision. This needs to change and one instrument to implement the change is the Pro-
fessional Doctorate (D.Prof.).
Why is the D.Prof. the solution? In many systems the opportunity for curiosity-driven and practice-based tradi-
tional Ph.D. research in operational laboratories has been lost or is absent. In the UK the traditional Ph.D. offered by
universities has been criticized for not delivering a rounded graduate. It may not be possible to access or return to labo-
ratory facilities to undertake laboratory-based research in busy operational laboratories. The reasons for this are many
and include lack of time and instrumental resources and the need to maintain accreditation standards on instruments
used operationally with the consequence that they cannot be used for research purposes. Many of the criticisms levelled
at Ph.D. programs in the UK will be equally applicable in the U.S.
The solution to these difficulties may lie with the Professional Doctorate. A Professional Doctorate “is a program
of advanced study which, whilst satisfying the criteria for the award of a doctorate, is designed to meet the specific needs
of a professional group external to the university” (UKCGE, 2002: 62). It is a part-time route to a doctorate specifi-
cally designed for busy senior practitioners who have already accrued considerable professional experience during their
working lives. The focus of the professional doctorate is on the needs of the candidates, their host organization, and the
wider professional community.
However, a problem at work may not always be a research-worthy one. A doctoral research-worth problem will
need a “yes” answer to one of the following questions:
1. Will a known gap in the body of knowledge be filled?
2. Will previous research be replicated and expanded by looking at a different category of participants, environment,
and/or constructs/variables?
3. Will previous research be expanded by more thoroughly examining some identifiable aspect?
4. Are there specific, identifiable, and documented problems with the currently available solutions?
The subject of study usually relates to an area of professional practice—for example resource allocation, laboratory
design, or policy implementation rather than a detailed scientific problem. For the D.Prof. candidate, it can take con-
siderable time to develop a problem-based research focus before embarking on the research in detail. It is for this rea-
son that the doctorate at Anglia Ruskin University is divided into two parts—Stages 1 and 2. Stage 1 involves the
development of the research proposal through 7,000 word essays. The first of these is a reflective document identifying
the professional issues that will be addressed in the course of the research. The second paper addresses the “state of the
art” and comprises a comprehensive literature survey around the issue to be addressed. The final paper describes the
8 Forensic Magazine I www.forensicmag.com JUNE | JULY 2012
viewpoint of
The Case for a Professional
Doctorate in Forensic Science
Michael Cole
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12. 12 Forensic Magazine I www.forensicmag.com JUNE I JULY 2011
Chris Asplen
AdynamicfairlyuniquetotheU.S.systemofjusticeistheexten-
sive impact that victim advocacy has on policy, legislation, and
funding. Having lived and worked abroad for more than a few
years,I’vebeenstruckbytheextenttowhichvictim’svoiceselse-
where fail to resonate with decision makers the way they do in
theUnitedStates.It’snotthatvictimadvocacyisnonexistentin
other parts of the world but the impact victims have in the U.S.
for the cause of justice can be extraordinary.
NatashaAlexankoisoneofthosevoicesfightingforjustice.
WhilethecommunityofDNAactivistsisalreadywellrepresent-
ed by tireless advocates like Debbie Smith who has battled for
years to ensure sufficient DNA funding and Jayann Sepich who
criss-crossesthecountrytopromotearresteetesting,Natashahas
madethecommitmenttodedicatehertime,effort,andherstory
specifically to the elimination of backlogged rape kits. A victim
whose rape kit sat untested for nine years, Natasha has started
Natasha’s Justice Project, dedicated to eliminating the estimated
200,000 kit backlog of rape kits through education, advocacy,
and public awareness.
Natasha’sstoryissorelevantandrepresentativeoftheinjus-
ticeofuntestedrapekitsthatitwasusedrecentlytopunctuatean
HBOfilmproducedontheworkoftheManhattanDA’sOffice’s
Sex Crime Unit. Simply titled, Sex Crimes Unit, the film docu-
ments the daily work of prosecutors and investigators navigating
theveryrealisticwatersofbringingamassivenumberofrapiststo
justice.Natasha’sstoryisthreadedthroughoutthefilm,highlight-
ing a particularly difficult aspect of sex crime investigation and
prosecution—the cold case. A stranger rape, with little evidence
other than DNA, but DNA evidence rendered useless by the
failure to have it submitted, analyzed, and entered into CODIS.
What her story highlights, and what she now brings to the
advocacy community, is the story behind the headlines or the
CODIS statistics. It is the value in all victim advocacy. It is the
meaningofsolvingacasetoavictim’ssenseofself,ofsafety,relief
ofguiltthattheycouldhave,shouldhavedonesomethingdiffer-
ently. It is the opportunity to have what Natasha called that
“transcendent”momentofclarity,andmostofallpower,fromthe
witness stand. Clarity and power that is denied as long as a case
remains unsolved.
In 1993, Natasha was a twenty-year old college student liv-
inginNewYorkCity,adreamshehadmaintainedherentirelife.
She was violently raped, sodomized, and robbed at gunpoint by
an unknown assailant while walking back to her apartment.
Natasha resisted the temptation to shower the evidence away
from her violated body and went to the hospital where hospital
staff collected evidence for her rape kit. Following her assault, all
leads were exhausted by the New York City Police Department
andherattackercouldnotbeidentified.Natasha’srapekitsaton
a shelf at the New York City Police Department property clerk’s
office for the next nine years.
To be clear, Natasha’s case was not the result of a systemic
failuretoactbypolice,prosecutors,orthelaboratory.(Ifyouread
thiscommentaryevenoccasionally,youknowIhavenoproblem
pointingoutsuchfailurewhereIthinkitexists!)Thesewerestill
the early days of DNA databasing. The New York City Medical
Examiner’s Office was not even a part of CODIS yet. Not sub-
mittingarapekitforDNAanalysiswasanunderstandable,albeit
frustrating, decision for police at that time. If no suspect existed,
fundsspentonDNAanalysiscouldfairlybeconsideredwastedif
no suspect was ever developed through other, more traditional
evidence. But again, this was pre-CODIS.
Then, in 2003, Mayor Michael R. Bloomberg announced
the “John Doe Indictment Project,” a coordinated city-wide ini-
tiative designed to prevent rapists from using the statute of
limitationstoescapeprosecution.Of17,000untestedrapekits,it
was estimated that an excess of 600 cases related to those kits
were soon to expire, including Natasha’s case. As a result, nearly
a decade after her attack, Natasha received a call from the New
York City District Attorney’s Office as prosecutors looked to use
the DNA from her rape kit to create a “John Doe” indictment.
That same year, summoning more than just a little courage, she
testified before a grand jury and the DNA profile from her rape
kitwasindicted,allowingprosecutorstobringchargesagainsther
attacker whenever captured.
In 2007, the New York City Police Department found
Natasha’s attacker through a match to his DNA profile in
CODIS.VictorRondonhadbeenarrestedinLasVegas,Nevada,
onaminorcharge.WhenextraditedtoNewYork,hisDNApro-
file was entered into CODIS pursuant to a parole violation.
Rondon’s profile matched the DNA profile developed from
Natasha’s rape kit. A year later, Rondon was tried before a jury
and found guilty of eight counts of violent assault, including bur-
glary in the first degree, robbery in the first degree, two counts of
rape in the first degree, sodomy in the first degree, and sexual
abuse in the first degree. Rondon was sentenced to 44 to 107
years in prison.
DNA Activism
dnaconnection
the
13. That’s not to say her trial was anything less than traumatic.
The first question on cross-examination was, “Were you a virgin?”
Seriously. In today’s world, with a Rape Shield law firmly in place
inNewYork,thatwasthefirstquestionoutofthedefenseattorney’s
mouth. (A woman described by the prosecutor as an experienced
defenseattorneywithaclearknowledgeoftheobjectionablenature
of the question.) The cross-examination didn’t get better from
there.Thedefenseprofferedbythedefendantwasbasedonthethe-
ory that, since Natasha didn’t scream while
shewasshovedupthestairsofherapartment
building into the bike storage area, thrust
over a railing, and repeatedly raped and
sodomized WITH A GUN TO HER
HEAD, well then clearly she must have
enjoyed the experience and that constituted
evidence of consent.
Getting back to the film. There was
another poignant observation to be made
about the film. As Natasha’s story unfolds
and it becomes clear that it was nine and a
half years that her rape kit sat untested, the
director uses flashes of newspaper articles
withheadlinesaboutsexcrimesandrapekits
and backlogs. But while the headline was
clearly visible, you could also see a bit of the
text from the article. And in those flashes of
textyoucouldseeanamerecurringtimeand
time again—Debbie Smith. Debbie Smith
for whom the Debbie Smith Act is named
and who is responsible for literally hundreds
of thousands of dollars allocated to various
aspects of DNA testing. Coming full circle,
the film reminds us, although I think unin-
tentionally, that it was victim advocacy that
first forced decision makers to pay attention
to the issue of backlogged rape kits and the
tragedy of solvable yet unsolved cases. It was
Debbie’s victim advocacy that drove the
decision makers to test Natasha’s kit in the
first place.
Natasha was raped when there were
legitimate reasons that made the decision
not to test a rape kit rational. Lack of a fully
implemented CODIS system made those
decisions understandable. In 2012 however,
there are no understandable or rational rea-
sons why 200,000 kits remain untested.
There is no cost benefit analysis that comes
outonthesideofrefusingtosubmitacaseto
the laboratory. Fortunately, there is now yet
another loud and convincing voice willing
toshareherstoryandtestifytotheunaccept-
able fact of backlogged rape kits.
Thank you, Natasha.
Chris Asplen is President of Asplen and Associates, LLC. He
consults with local, state, federal, and international governments on the
use of forensic DNA technology. He can be reached at
ChrisAsplen@Gmail.com.
continueddnaconnection
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JUNE I JULY 2012 Forensic Magazine I www.forensicmag.com 13
15. Suppose, just after the Fourth of July fireworks begin on the Charles River, a team of terrorists located 100 meters apart
along Boston’s Esplanade simultaneously empty several canisters of the odorless nerve agent sarin on the ground
amongst the holiday crowd. The liquid agent quickly evaporates into a deadly, invisible vapor, spreading through the
crowd. Within seconds symptoms appear in the hundreds of people exposed—blurred vision, drooling, sweating,
coughing, chest tightness, breathing difficulty, nausea, and diarrhea. Those exposed to more concentrated amounts
experience loss of consciousness, convulsions, paralysis, and respiratory failure.
In the growing confusion and panic, the terrorists slip away into the night, undetected. Apprehension, prosecu-
tion, and imprisonment are not likely. No one noticed them. Everyone was watching the fireworks. Police have no
leads.
Or do they? The developing field of chemical forensics may offer clues.
Government scientists, led by chemist Carlos Fraga at the Pacific Northwest National Laboratory, are reporting the
development of a unique chemical forensic tracking technology that could help law enforcement trace the residues from
terror attacks involving nerve gas and other chemical agents back to the companies or other sources where the perpetra-
tors obtained ingredients for the agent.
Nerve substances, such as sarin, are among the most toxic and fast-acting chemical warfare agents in existence.
Sarin is lethal in amounts as small as 36 ppm. A single drop of sarin the size of a pinhead can kill an adult, as the
Japanese learned in 1995 when the Aum Shinrikyo religious sect released sarin in the Tokyo subway, killing 13 and
injuring over 5,500.
Although traces of nerve agents remain after such attacks, prior to Fraga’s work there has been no practical way of
tracing the agent back to its source ingredients. Fraga’s team found a way to do that using a technique called “impurity
profiling”—a way of identifying impurities in chemicals or illegal drugs that allows the chemical to be matched to the
impurities in the precursor chemicals, pinpointing the likely source. Impurity profiling has been used for several years to
track seized drugs, helping law enforcement determine dealer-user relationships, drug sources, distribution networks,
and smuggling routes by connecting seized drugs to precursors.
Impurity profiling also has the potential to trace counterfeit pharmaceuticals and herbal medicines, banned pesti-
cides, and homemade explosives.
Fraga adopted the technique to track nerve agents like sarin because of the high threat of a terrorist chemical
attack. The researchers found that up to 88% of the impurities in source chemicals used to make sarin appear also in
the finished product, and that these impurities are unique, much like fingerprints.
“This means potentially tracing a chemical threat agent like sarin to the specific lot number and commercial man-
ufacturer that produced the precursor used to make the sarin collected from a crime scene,” Fraga said. Once the manu-
facturer of the precursor is known, then purchasing and shipping records may point to the buyer.
Fraga said that to his knowledge, this is the first time impurities have been demonstrated for matching a synthetic
chemical product to its specific precursor source.
This new piece of evidence obtained through impurity profiling could provide useful leads that complement those
obtained by traditional pieces of crime-scene evidence, like latent fingerprints, trace DNA, and camera footage.
Kevin Lothridge, CEO, National Forensic Science Technology Center, said Fraga’s technique is the same concept
as the Drug Enforcement Administration’s cocaine, heroin, and methamphetamine signature programs. “This type of
JUNE I JULY 2012 Forensic Magazine I www.forensicmag.com 15
Douglas Page
Amazing TraceNew chemical forensics test could help track down terrorists responsible
for nerve gas attacks.
16. forensic intelligence can be useful in a range of
investigations, from drug cases to terrorism,”
Lothridge said. “It adds another technique to the
analytical toolbox to help investigators advance
the intelligence they are able to gather.”
Nothing Special
The PNNL method requires no special equipment,
other than standard laboratory gas chromatogra-
phy/mass spectrometry instruments.
“What is most remarkable is that the chem-
ical impurity profiles can be recovered mostly
intact from sarin samples even after multiple
processing procedures, such as distillation and
two solvent extraction steps,” Fraga said.
Fraga said this development is important
for a couple of reasons. First, he said he hopes
that this and similar work will deter future
chemical attacks by letting terrorists know
there are now ways to track them.
“Second, by developing a forensic capability,
we have a greater chance of finding perpetrators of
chemical attacks or their sources of materials before
they can strike again,” he said. “And third, our work
can potentially be applied to other threats, such as
illicit drugs and homemade explosives.”
Lawrence Kobilinsky, chair of the Department of
Sciences at John Jay College of Criminal Justice, believes
Fraga may be on to something valuable in the fight against
terrorism.
“This work promises to provide a new approach to
fighting chemical terrorists and chemistry-oriented crimi-
nals,” Kobilinsky said.
While sarin attacks have not yet occurred in the
U.S., they could at any time. Kobilinsky said terrorists
would not think twice about using biological, chemi-
cal, or radiological weapons to cause mass destruc-
tion of populations in Western nations. “The
anthrax attacks were a wake-up call for law enforce-
ment and homeland security,” he said.
In the event of a nerve agent attack,
Kobilinsky said authorities must neutralize the
effects of such attacks and ultimately trace the
source of the weapon. Sometimes, different groups
claim credit for a terrorist attack when it is clear
that only one group was responsible. “This tech-
nique can help assign blame on those who are truly
responsible for a chemical attack,” Kobilinsky said.
Origin of Impurities
Rashid Chotani, MD, director, Chemical and Biological
Defense Programs at TASC (Chantilly, VA), said in order
to validate impurity profiling in the context of chemical
warfare, the researchers may need to explore the origins of
the impurities to increase the confidence of their results.
“Given the number of sources for agents and precur-
sors—in the U.S. alone about 100 facilities deal with chem-
icals that are ‘scheduled’ under the Chemical Weapons
Convention—this new technique would work best when
traditional forms of investigation have narrowed the sample
size to a few possible locations,” he said.
Chotani said this technique could potentially enable
investigators to link the agent back to a specific laboratory,
assuming that sufficient precursor materials remain in the
laboratory to identify any impurities.
Fraga concedes his work is in the preliminary, proof-of-
concept stage of development, that there is a great deal of
work required to determine what can and cannot be done
with impurity profiling. He said one of the first tasks is to try
to understand the sources and causes of variability for the
impurity profiles obtained from chemical agents and their
precursors, a step necessary to quantitatively determine if
the impurity profiles from different samples match and what
the error rates are if the profiles match.
In the near term, Fraga proposes to combine the impu-
rity profiles obtained for sarin and precursors with other
impurity profiles and chemical characteristics that are not
being captured by current analytical approaches.
“We anticipate that these new measurements will
independently make the same connection we made
between sarin and its specific precursor stocks, thereby
increasing the level of confidence in a match,” he said.
Fraga does not wish to over-sell his technique nor see
its value reduced, like that of compositional analysis of bul-
let lead (CABL). CABL is similar to impurity profiling in
that the chemical components present in bullet lead can
provide forensic information.
However, according to a 2004 report (Weighing Bullet
Lead Evidence, The National Academies Press) CABL has
been over-sold in court and therefore its usefulness and
credibility has diminished, Fraga said. “We are therefore try-
ing hard to understand the limitations of impurity profiling
to avoid over-selling it.”
Douglas Page writes about forensic science and medi-
cine from Pine Mountain, California. He can be reached at
douglaspage@earthlink.net.
16 Forensic Magazine I www.forensicmag.com JUNE I JULY 2012
19. Fingerprints are considered one of the most reliable ways to identify individuals associated with criminal cases.
However, sometimes they cannot be recovered due to various environmental factors. One of these factors is tem-
perature, specifically high temperatures. At high temperatures the water left by fingerprints evaporates and the
amino acids denature. In this experiment, the optimal temperature ranges for a sheet of computer paper and plastic
bottle was found to be from -20°C to 185°C for a 15 minute exposure to heat and from -20°C to 150°C for an hour
exposure to heat.
Background
Fingerprints are widely accepted as being a unique characteristic of a person. Kaushal states, “No two people, not
even identical twins, have ever been shown to have exactly the same pattern of raised, curved lines on their finger-
tips.”1 These patterns on the fingertips, called minutiae, are special to each individual person. When a person
touches a surface, a chemical mixture of their fingerprint is left behind called an impression, which refers to the fric-
tion ridge detail deposited on the surface. If this action is unintentional, it is called a latent print. In most cases, fin-
gerprint examiners deal with latent prints. The mixture that makes up these impressions include water, amino acids,
cholesterols, fatty acids, small-molecule oils, DNA, and ionic salts.2 Forensic scientists use numerous techniques to
react with these chemicals and make the latent print visible to the naked eye.
Several factors can alter or disrupt these chemicals and therefore make the latent print unidentifiable to an examiner. The
temperature of the surface on which a latent print is left is one such factor.3 A higher temperature would cause the water to evapo-
rate and cause the amino acids to denature. This can make the latent print hard to visualize and extremely difficult to identify. A
study done by William and Karen Sampson4 suggests that the optimal temperature ranges for identifications are from 68°F to 95°F
(20°C to 35°C). The study suggested that if a latent print was exposed to heat or dryness for hours to days, it would be hard to
retrieve the print.
The purpose of the present study is to deter-
mine the optimal temperatures in which a latent
print can be recovered from a piece of computer
paper and a plastic bottle. Paper and plastic were
chosen because they are commonly handled by
individuals on a daily basis. Also paper and plastic
are commonly found at crime scenes. Once the
range is determined, the time period in which the
latent print endures those temperatures will be
extended to see if the range shortens.
Materials and Methods
The experiment was conducted using two of the
Hamline University Chemistry Department’s
ovens, Furnatrol I Type 18200 Automatic
Controller Model FA1730 and Fisher Scientific
Isotemp Oven Model 630F. The temperature was
set to 33°C on the oven and then allowed to pre-
heat. Once the temperature was reached, latent
prints were placed all over the sheet of computer
JUNE I JULY 2012 Forensic Magazine I www.forensicmag.com 19
Anthony Iten
OptimalTemperaturesfor
LatentPrintRecoveryA study on the effects of time and temperature on the recovery of
latent prints from computer paper and plastic bottles.
Figure 1: Dusting results of paper and plastic bottle at 90°C for
15 minutes (positive). View a slideshow of the full results above
or at www.forensicmag.com/article/optimal-temperatures-
latent-print-recovery.
20. paper and the top of the plastic bottle. To ensure a good print, the fin-
gertips were rubbed along the forehead and sides of the nose. This
allowed the fingertips to collect more water, amino acids, and oils. Once
the latent prints were placed on the computer paper and plastic bottle,
the computer paper and plastic bottle were placed inside the oven for
approximately 15 minutes. After that, they were transferred to a large
plastic container and sealed inside. This helped keep the computer
paper and plastic bottle at the same temperature as the oven. The con-
tainer was then transferred to another building where the super glue
fuming chamber was located, as shown in Figure 2.
Four drops of liquid super glue were placed on the aluminum foil
cup, which was then placed on top of a heating pad inside the chamber.
A hot cup of water was also in the back corner of the chamber. The
piece of computer paper was then clipped to the top of the chamber and
the plastic bottle was placed in the other back corner. Next the heating
pad and light were turned on and the chamber was closed. The paper
and plastic bottle were exposed to super glue fumes for 15 minutes.5
After that the chamber was opened and the heating pad was turned off
to allow the fumes to evaporate. This causes the chemicals left behind by
the latent print to condense and become hard. It allows the latent print
to be dusted without smudging the print. Then the piece of computer
paper and plastic bottle were dusted using Black Magna Fingerprint
Powder to reveal an impression if there was any. A picture was then
taken of the result of the dusting. The same test was performed at the
temperatures of -20°C (obtained by using a freezer), 20°C, 40°C, 60°C,
90°C, 110°C, 160°C, 185°C, and 220°C. Then the temperatures of -
20°C, 120°C, 150°C, and 170°C were tested again, but left inside the
oven for one hour.
Results
Pictures were taken after each dusting was completed on the sheets of
computer paper and plastic bottles. The temperatures for the 15 minutes
intheovenareshowninFigure1(printswithvisibleminutiaearelabeled
positive and non-visible prints are negative).
The temperatures for the one hour in the oven are shown in
Figure 3 (prints with visible minutiae are labeled positive and non-visi-
ble prints are negative).
Althoughthepicturesmaynotshowitattimes,theoptimaltem-
peraturerangefor15minutesintheovenwas-20°Cto185°C.
Temperatureshigherthan185°Cturnedthecomputerpaperbrittleand
brownmakingitimpossibletorecoverimpressionsbydustingthem.It
wasalsoimpossibletorecoverimpressionsfromtheplasticbottleatthose
hightemperaturesbecausethebottlemeltedcompletely,whichwassur-
prisingbecauseittookonlyashorttimeforthemtomeltcompletely.
Furtherresearchaboutthetemperature at which plastic melts would have
helped determine when the plastic bottle would have melted. When
testing the latent prints for an hour inside the oven, the -20°C test
showed that impressions could still be recovered. However, when the
latent prints were tested at 170°C, the computer paper became brittle
again and the plastic bottle was partially melted. There were some minu-
tiae on the plastic bottle but most of the impression was blurred together.
The computer paper impression was blurred completely. When the com-
puter paper and plastic bottle sat inside the oven for an hour at 150°C,
the super glue fuming and dusting process was able to reveal impressions
on both.
Discussion
This research had many possible sources of error. To begin with,
the oven would sometimes change temperature throughout the
time the computer paper and plastic bottle were inside. It seemed
that once the items were placed inside the oven, the temperature
increased periodically. For some of the tests, the temperature
would increase only a few degrees but in other tests it increased as
much as 15 degrees. This increase in temperature may be due to the
make and model of the oven. More tests could be conducted to
solve this problem by using a better, stable oven. The increase in
temperature could have affected the true temperature at which
the items were tested and therefore affected the optimal temper-
ature range. Another source of error was the time the computer
paper and plastic bottle were super glued. It is possible that the
items were not super glued long enough, making the impressions
more prone to be smudged when dusting. This again would pro-
vide negative feedback on the optimal temperature range. The
amount of time items are super glued depends on the number of
items present in the chamber.6 With many items, super glue
fuming can take up to 45 minutes.
This research can be applied when dealing with crime scenes
that have been exposed to extreme temperatures. When examiners
know the crime scene exceed a certain extreme temperature, then
they know that an impression cannot be recovered from an object.
However this research only pertains to computer paper and plastic
bottles. To make this study more applicable, other surfaces must be
considered and tested. For example, different kinds of paper and
plastic, metals, rubber, wood, and glass would be suitable items to
test. Another area worth exploring is if it is possible to recover
impressions from fired bullets and casings along with explosives.
ATF conducted a study on Molotov cocktails and were able to
20 Forensic Magazine I www.forensicmag.com JUNE I JULY 2012
Figure 2: Super glue chamber in Drew
Science Center Room 205.
21. JUNE I JULY 2012 www.forensicmag.com I Forensic Magazine 21
recover some impressions on the glass fragments.6 A future
direction in this area would be to study plastic explosives.
Conclusions
Forsomesurfaces,therearetemperaturesbeyondwhichlatentprints
canberecoveredthusmakingitimpossibletogetanimpression.The
longerthelatentprintisexposedtoheat,themaximumtemperature
tovisualizethatimpressiondecreases.Thesemaximumtemperatures
may vary depending on the surface they are tested on, but were the
sameinthisstudy.At15minutesofexposuretoheat,computerpaper
and a plastic bottle had a maximum temperature of 185°C. For an
hour of exposure to heat, paper and plastic had a maximum temper-
atureof150°C.Thereforeitisreasonabletoconcludethatasthedura-
tion of time spent at temperature increases, the shorter the tempera-
ture range is to obtain an identifiable latent print. Further research
would be needed to solidify the exact temperature ranges.
References can be found online at www.forensicmag.com/
article/optimal-temperatures-latent-print-recovery.
Anthony Iten is recent graduate of Hamline University
with a B.A. in Chemistry and a Forensic Science Certificate. 624
Community Dr., Morgantown, WV, 26505; (612-790-0974);
aiten01@hamlineuniversity.edu.
Figure 3: Dusting results of paper and plastic bottle at 120°C for
one hour (positive). View a slideshow of the full results above or
at www.forensicmag.com/article/optimal-temperatures-
latent-print-recovery.
23. Traditional definitions of “evidence” include the
ideas, “to make evident, something that makes
plain or clear, data presented in court in proof of
the facts.” (Dictionary.com) If a picture is “worth
a thousand words,” and if the definitions above
are some of the ways that we define the term
“evidence,” then I would like to suggest some
perhaps new ways that we can use this vital
unappreciated tool.
The idea that the only time that one takes
pictures is when there is a need to document a
broken window, skid marks, vehicle damage,
wounds, or injuries needs to be revisited, especial-
ly at the “patrol level.” Photography or digital
imaging can certainly be an effective tool to doc-
ument “evidence” that can save you time and
effort down the road.
Traffic Enforcement
Those of you who stop vehicles for equipment and safety violations probably spend a great deal of time writing out a three
paragraph description of the violations that initially caused you to stop the vehicle, and the subsequent violations that you
discovered (Figure 1). If, down the road you need to defend your stop and the reasons you took an enforcement action
doesn’t it make sense to have a photo or at least three to back up your observations and narrative report.
Instead of trying to create a word picture on the witness stand to help the judge or jury to “see” what you saw, why
not let them do just that—see what you saw; because after all, seeing is believing right? Having photographs to supple-
ment testimony regardless of the case is like conveying the message to the judge or jury that “you don’t need my testimo-
ny, have a look for yourselves.” And if you stop and think about it, the
proverbial “picture is worth a thousand words,” is also worth at least 45
minutes of direct, cross examination, and re-direct testimony in court
when you could be enjoying your day off.
If the tires were “as bald as a baby’s behind” then you would most cer-
tainly benefit from having a photo to back up that contention (Figure 2).
Isn’t this a better way to work? Can you see where a few images can save
you from even going to court at all, much less invariably in the middle of
your days off?
Eyewitness Perspective Documentation
We have all had cases where that one witness seems to make the case. So
suppose for a minute that our case is one where a witness saw a suspicious
person behind a business who appears to be ready to rob the business. The
JUNE I JULY 2012 Forensic Magazine I www.forensicmag.com 23
Mike Voelker
Evidence Photography:
Thinking Outside the Box
Photography illustrating your case report can strengthen your case and
corroborate your narrative.
Figure 1: A photo can illustrate vehicle safety violations.
Figure 2: Show don’t tell.
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26. caller reports that the person appears to have a shiny object that
looks like a firearm of some sort. Suppose that officers who are sent
to investigate the subject end up shooting the subject who was
“armed” with something other than a weapon.
Having initial responding officers document where and how the
witness saw what they reported is obviously vital to any case. Instead
of simply having the witness testify that they were looking out their
window through the slats in their window blinds, again take the jury
to the scene (Figure 3). Supplement the witness’s testimony with an
image for the jury to take to the deliberation room.
Just to make sure that we are being as thorough as possible
when we are locating where the suspect was at certain times in the
event, suppose we use a traffic cone from our squad car or partner
officer positioned by the witness from their perspective to further
solidify and document that they had the ability to make their obser-
vations. Taking the picture to show where the witness was making
observations can also aid their recall at the time of trial some years
down the road.
Now let’s think about what effect the photos will have if we
take it a step further and allow the witness to use our patrol point-
and-shoot camera to take a picture framing it with the perspective
that they saw. As noted speaker and forensic innovator Dick
Warrington says, “Who says you can’t do that?” While this is certain-
ly unconventional, I think your prosecutor has an even firmer foun-
dation to introduce the images of the witnesses view to show that
they had the perspective to see what they are testifying to.
Use of Force Documentation
At times people will make frivolous claims of excessive force and
injuries resulting from arrests and uses of force in an attempt to solve
their financial problems. Have you thought about how photography
can back up your narrative report and how little appreciated and
understood aspects of digital photography can save you, your co-
workers, and your department time, effort, and perhaps money?
Let’s use an example of a use of force event where you or your
co-worker’s suspect ends up with injuries that need to be treated at a
hospital or otherwise have the person medically cleared before taking
them to jail. I think most of us would think to take pictures of the
wounds, but let’s look past the obvious and document the snugness of
the handcuffs to cover that base as well. If the suspect is going to con-
tend in a civil suit that you or your co-worker were vicious and out of
control, would an officer who is busy snapping a series of pictures seem
out of control to a jury?
Now let’s factor in the often overlooked aspect of the date and
time stamp which is part of the digital image file metadata. If your
camera has been adjusted to the correct date and time prior to taking
the images, then your images can essentially take the jury to the scene.
On this date and time this image was created and was saved to the SD
card in this camera.
Absent in-squad video to back up your report that the suspect was
spitting what they claim was contaminated blood at you while being
transported; use a few photographs to document that the suspect had
indeed done just that (Figure 4). Correctional staff documentation of
claimed wounds or injuries on intake to the facility can help refute friv-
olous claims. The photographs document what the subject and their
injuries looked like on this date and at this time.
A good personal, if not departmental practice would be to take a
series of pictures the minute the suspect makes a comment about the
handcuffs being too tight. After arrest and booking into the jail at least
a second set should be taken.
Evidence Packaging
If there were questions about how you packaged your evidence, you
can certainly answer nearly all questions without having to check the
evidence out of property, remove the items for photography, and
then add another seal when you re-package the evidence—if you
took images of how you packaged and sealed your evidence. While
this certainly adds a bit more time at the forefront of the investiga-
tion, I would argue that this will save you time and effort later on as
you won’t need to explain the multiple layers of evidence seals on a
particular package on the stand.
Here again I feel that your friend and mine, the date and time
stamp on digital images, can bolster our position that we are not
26 Forensic Magazine I www.forensicmag.com JUNE I JULY 2012
Figure 3: Photographing the eyewitness’ perpective takes
the jury to the scene.
Figure 4: Images can help combat frivolous use of force
claims.
27. making it up. With a series of images you can lay out in order, on this
date and time here is the seal that I put on the package, then on this
date and time this seal was put on, followed by this one. I don’t mean
to belabor the point, but as our society becomes more visually orient-
ed, I think we do our cases a disservice if our only testimony to the
truth of the matter is “well, I’m telling you it was this and I am sworn
to tell the truth.”
Drug Evidence
Photographs could probably save you from testifying in court by tak-
ing a few pictures of the material at the time of discovery, the subse-
quent field test results, and the packaging of evidence.
With a few pictures and some basic subject and case informa-
tion a prosecutor could literally dictate a criminal complaint just
from your images. For example in these next two images you visually
depict what the subject was possessing, the officer notes the total
amount of currency by (Figure 5) writing it next to each denomina-
tion stack. Next the officer has tallied up the total currency amount,
and then written the weight of each of the individual baggies by each
baggie, followed by the weight of the larger container baggie (Figure
6) to provide even more detailed documentation. In most jurisdic-
tions juries are not allowed to review police reports during delibera-
tion, but they certainly could be allowed to have your evidentiary
photographs to review.
Taking our “evidence photography” thought process to
another level, how about documenting the weight of our contra-
band with a photograph in a new way. Again the side benefit to
digital photography is that bleary eyed investigators can readily
determine when during that 36–48 hour work day they were pack-
aging that particular evidence by reviewing the date and time
information which is part of the digital image data (Figure 7).
After presenting this at my department I heard that an offi-
cer took this to the next level by taking a picture of the scale face
before weighing the material. The image showed a .00 gram
weight followed by a picture of the evidence and the weight of
that evidence. While this seems a bit odd, it can help refute any
defense contention that the scale
was not working properly and was
not zeroed out before you weighed
the item. The date and time infor-
mation, along with the image
number, will back up when the
image was taken.
The images don’t have to be
the greatest thing since sliced
bread, they just need to back up
your observations and narrative
report.
Vehicle Searches
Juries know from media sources that
we tend to find a treasure trove of
contraband in the center console of
vehicles. Squad video footage can
back up the fact that we were in the car empty handed then pulled
out something and placed it in an evidence bag. But now with our
new or renewed method of taking the jury to the scene let’s take a
few pictures before, during, and then after the vehicle search (Figure
8). Having a picture of what we found, how we found it, with the
correct date and time stamp as to when we found it—followed by
post search photos showing that the K-9 did not claw up the interior
of the car during the search—I think closes the door on a great num-
ber of issues that arise and confront us regularly. At the next level, if
your camera supports and captures geopositioning data you can now
“show” the jury nearly exactly where that traffic stop took place or
where the images were taken. Officers who work in rural areas can
certainly see the tremendous benefit to this.
JUNE I JULY 2012 Forensic Magazine I www.forensicmag.com 27
Figure 5: The officer notes the total amount of currency
confiscated.
Figure 6: Documenting the weight of each individual baggie.
Figure 7: Give the jury a
failsafe visual: showing just
how much the drugs
weighed.
Figure 8: Take a few pictures before, during, and after a
vehicle search.
28. 28 Forensic Magazine I www.forensicmag.com JUNE I JULY 2012
Electronic Evidence Documentation
Amongst the problems confounding our best efforts to gather this
data is the cost of the extraction devices, and sometimes the distance
between the extraction device and the subject device.
Whether it is the temporary threat posted on Facebook, the
threat, or the no-contact violation sent via a text message, low cost
point-and-shoot style digital photography can be an effective tool for
officers or investigators in the field to capture and document evi-
dence. A background of a brown paper evidence bag, coupled with
the business card with the case number and investigator’s name in at
least one of the images will demonstrate a level of professionalism.
First Responder Photography
Finally it probably goes without saying that it is extremely vital for
initial responding officers to take at least a few photographs of scenes
before they get contaminated by personnel conducting a walk-
through. The few minutes of time to take a set of overall and mid
range views of a scene can not only provide images to brief respond-
ing investigators, they can steer an investiga-
tion on a logical course from the start.
I know of a department where a number
of years ago a full complement of personnel
were called in to investigate a body found in
the basement storage area of an apartment
building. The limited information available was
that the area by the body was extremely bloody.
Once the documentation of the scene
leading to the body was complete, a more thor-
ough exam of the specific scene clearly showed
that instead of a homicide the department was
dealing with a very determined and indeed very
bloody self-mutilation suicide event. The inves-
tigation showed that the subject clearly lost
consciousness after cutting himself, laid down
several times, and then would get up again and
run around the same area in a circle trying to
pump his blood.
Clearly, a few scene photographs to brief
the investigative team could have focused the
investigation from the onset and likely could
have saved time, pages of reports, and the cost
of personnel for that department.
It is my hope that you can see the benefits
of having still images to supplement your work
and reports, and I have no doubt that in addi-
tion to what I have suggested here, you have
already thought of additional ways a series of
pictures could have improved an investigation.
Take a few minutes and share that information
with your co-workers and contacts.
Mike Voelker is a Detective with the Eau
Claire, Wisconsin, Police Department. Det.
Voelker has over 23 years of law enforcement expe-
rience. Eau Claire Police Department, 740 Second
Avenue, P.O. Box 496, Eau Claire, WI 54702-
0496; (715) 839-6165;
mvoelker@eauclairewi.gov;
www.eauclairewi.gov/police-home.
Visit www.labconco.com or call
1-800-732-0031 for more information.
Freedom for the good guys—conviction for the bad guys.
The Protector® Downdraft Powder Station keeps users
safe by containing powders during fingerprinting processing.
www.labconco.com
Protector® Downdraft
Powder Station
29.
30.
31. With modern technology, the simple act of picking up an object or touching a surface can lead to the identification and apprehen-
sion of a criminal. In the past few years, not only have the number of touch DNA evidence items being submitted to the lab for
analysis skyrocketed, but the number of journal articles regarding touch DNA and DNA transfer (both primary and secondary) has
also increased greatly. This article is intended to update the reader on the latest touch and transfer DNA research and attempts to
answer some of the most common questions that are asked regarding the topic.
What is “touch” DNA?
First, a review of what touch DNA is and how it arrives on an object. Touch DNA is simply DNA that is transferred via skin cells
when an object is handled or touched. The average human sheds roughly 400,000 skin cells per day;1 however, since it is known that
the top-most layers of skin are basically “dead”, being keratinized and having lost their nuclei,2 where does the touch DNA come
from? Kita, et al,2 performed experiments which showed that small amounts of fragmented DNA are present on the surface of the
skin and they theorized that these fragments of DNA may be constantly sloughed off the keratinized cornified layer of skin and that
sweat may also contain fragmented DNA. Later research verified that the presence of sweat helps to contribute to the DNA profile
obtained from touch DNA samples.3 This research also showed that cell free nucleic acids, or CNAs, (basically free-floating DNA
fragments not encapsulated in the cell nucleus) contribute greatly to the total amount of DNA present in a sample with CNAs being
detected in the sweat of 80% of healthy individuals tested. It was also found that, along with CNAs, nucleated cells were present in
sweat samples taken from volunteers. Interestingly, most DNA extraction methods do not utilize the portion of the sample where
CNAs are found—the aqueous portion of the extract—and after centrifugation to collect the cellular material, the supernatant (con-
taining the CNAs) is generally discarded.3
How much DNA is left behind when an object is touched?
One of the most common questions asked regarding touch DNA is, “how much DNA is expected to be transferred” given a certain
set of circumstances. Unfortunately, this is a difficult question to answer as there are so many variables involved. However, we can use
the information from various studies to provide an idea of how much DNA might be recovered from touched objects (Table 1).
Suzanna R. Ryan
Touch DNA Analysis:
UsingtheLiteratureto
HelpAnswerSome
CommonQuestions
Table 1: Summary of amount of DNA detected via contact.
Amount of DNA Mean Contact type/substrate Source
0 - 5.2ng 0.52ng glass held for 60s Daly, et al4
0 - 14.8ng 1.23ng fabric held for 60s Daly, et al4
0 - 169ng 5.85ng wood held for 60s Daly, et al4
0.16 - 6.4ng [blank] swab of hands Bright & Petricevic5
0-0.4ng [blank] fingers pressed on various substrates for 30s Alessandrini, et al6
0 - 50.8ng 1.7ng various volume crime evidence items Raymond, et al7
[blank] 4.3ng wallets held for 60s Raymond, et al7
3.1 - 33ng 11.7ng wallets held for various times Raymond, et al7
[blank] 17.8ng plastic knife held for 15 min. van Oorschot and Jones8
6.8ng [blank] mug held for 15 min. van Oorschot and Jones8
34ng [blank] glass held for 15 min. van Oorschot and Jones8
[blank] 51ng vinyl gloves worn for 20-90 min. van Oorschot and Jones8
[blank] 11.68ng cotton rubbed with palm, finger, and side of hand for 15s Goray, et al9
[blank] 0.396ng plastic rubbed with palm, finger, and side of hand for 15s Goray, et al9
JUNE I JULY 2012 Forensic Magazine I www.forensicmag.com 31
32. Is DNA always left on an object via touch?
It is important to note that not every contact leaves enough DNA
behind to yield a DNA profile. Often the question is asked, “If a person
touched this item, would they necessarily have left DNA behind?” The
short answer is no, not always. Journal articles regarding the transfer of
DNA have shown that DNA is not always transferred through contact
alone. Lowe, et al10 found that 12 of 30 subjects transferred little to no
DNA to a sterile tube after handling it for 10 seconds. A research arti-
cle by Rutty11 showed that of 29 simulated strangulation samples, only
19 yielded DNA results. Of these, only 7 showed signs of any DNA not
belonging to the victim. Phipps and Petricevic12 discovered that
51%–70% of individuals (depending on which hand was tested) failed
to leave behind their DNA on a sterile tube that was held for 10 sec-
onds. In addition, a study by Raymond, et al7 on trace DNA success
rates noted that of 252 trace casework samples (all from surfaces
touched by hands), 111 (44%) did not produce a profile.
It is important to take into account, however, the date the study
was published and what methodologies were used at that time, as
improvements in the technology and methodology of DNA analysis
have arisen. For example, many of the earlier touch and transfer DNA
articles report results from samples amplified with Profiler Plus and/or
COfiler which are older amplification kits that often used a larger
amplification volume (50 µl, as compared to the standard 25 µl reac-
tion volume of today’s kits) and required a split of the sample extract
into two amplification reactions. In addition, the majority of the earlier
papers list extraction volumes of anywhere from 50 µl to 200 µl. It was
not as common for the DNA extract to be concentrated to a smaller
volume (as little as 10 to 12 µl) as it is today, so it may be that addition-
al DNA profiles would have been developed in these earlier studies if
this concentration step had been performed. In addition, many labs
today have the option of using specialized techniques designed to maxi-
mize their DNA results. For example, in addition to concentrating
one’s DNA extract, the analyst may also have the option to increase
the injection time on the capillary electrophoresis instrument thus
increasing the amount of DNA entering the capillary for detection.
Additional Taq enzyme and the protein BSA (which helps overcome
PCR inhibition) can be added to the amplification reaction. Some labs
have the option to reduce the amplification volume even further (from
25 µl to 12.5 µl, for example), which has been shown to increase the
sensitivity of the reaction. In addition, the amplified DNA can be sub-
jected to post-amplification clean-up steps and additional amplified
product can be added to the sample tube for injection. Each of these
steps have the possibility of increasing the amount of DNA observed
on the resultant electropherogram, but it is important to be aware of
possible interpretational difficulties and stochastic effects that may arise
from using these techniques.
What factors tend to increase the amount of DNA
available for transfer?
Researchers aren’t exactly sure why sometimes DNA is transferred to
an object via touch and sometimes it is not. However, some known fac-
tors that can affect the amount of DNA available for transfer include:
• Shedder status. Several studies have indicated that some indi-
viduals may be considered “good shedders,” someone who tends to
slough or shed skin cells at a greater rate than others.10 However it
should be noted that the use of the terms “good” and “bad” shedders
has been debated as other studies have found that it is nearly impossible
to determine someone’s shedder status as repeat tests on the same per-
son on different days can give very different results.12
• Hand washing. Hand washing will remove many of the shed
cells leaving little DNA available for transfer.
• Personal Habits. Some individuals touch their face, eyes, nose,
hair, etc. more often than others, thus picking up DNA from those
areas to be transferred onto the next thing that is touched.
Wickenheiser1 described this as “loading” the fingers with DNA.
• Type of Contact. Factors such as pressure and friction can also
relate to how much DNA is transferred onto a touched object. An
increase in the amount of pressure applied tends to lead to an increase
in the amount of DNA transferred and the application of friction to
the contact increases the amount of DNA transferred even further.9
• Substrate. Rough surfaces (wood, concrete, grooved surfaces)
tend to collect and retain skin cell DNA better than smooth surfaces.
• Perspiration. It is thought that sweat can increase the amount of
DNA transfered for two reasons. First, as the sweat passes through the
pores and makes its way to the skin surface, it can collect cells along the
way and wash them to the surface.1 Second, it has been shown that
sweat also contains both epithelial cells and cell-free nucleic acids.3
Once the DNA gets there, how long will it stay?
Another common question when dealing with touch DNA is, “how
long does it last?” As with most questions relating to touch DNA, there
is no easy answer. Very little study has been done to assess the persist-
ence of touch DNA, but this is becoming an increasingly important
area of research, particularly as defense attorneys begin presenting argu-
ments to suggest that touch DNA found at a crime scene can be
explained by the defendant’s presence at the scene at an earlier time
that is unrelated to the crime at hand.
Consider the following scenario: A DNA profile matching a male
suspect is located on a brick wall outside the home of a murder victim.
The DNA appears to be from skin cells as it is negative for blood,
semen, and saliva. How did the DNA get there? The prosecution’s the-
ory is that the suspect fled the crime scene by climbing over the brick
wall. Considering that blood evidence matching the victim is found
nearby on the wall, this is a viable possibility. However, upon investiga-
tion, it is revealed that the suspect previously lived at the home in ques-
tion and is, in fact, a relative of the murder victim. Could it then be
possible that the suspect left his skin cell DNA at an earlier date when
he either lived at the home or visited his relative? How can we deter-
mine which of the scenarios are accurate?
Only one study this author is aware of directly addresses the per-
sistence of touch DNA. Raymond, et al,13 conducted an investigation
into the persistence of DNA at crime scenes. They applied known
quantities of “buffy coat” DNA (the white blood cell and platelet layer
of whole blood) to gloss-painted wooden window frames, pieces of
32 Forensic Magazine I www.forensicmag.com JUNE I JULY 2012
33. vinyl, and control samples. Not surprisingly, they found that the chance
of recovering DNA from an outdoor crime scene decreases significantly
over time with two weeks showing a significant drop in alleles detected
for most of the samples. The control samples fared much better, with full
profiles able to be developed even after six weeks (the longest time peri-
od tested). This study also provided a table of results obtained from actu-
al touch DNA casework samples and included the time between the
offense and the collection of the evidence. Great variability existed;
however, it is interesting to note that two of the three evidence items
with greater than 50 days between offense and collection yielded DNA
profiles. One additional study dealing with direct amplification of touch
DNA samples briefly discusses the stability of touch DNA on fabrics.
Volunteers rubbed their thumb and forefinger between a sample of fabric
for 5 seconds. The fabric samples were left exposed to light on a window
ledge and then subjected to direct amplification. Nearly complete
PowerPlex 16 profiles were able to be generated from touch DNA on
acrylic, nylon, and polyester for up to 36 days after transfer.14
To assess whether it is possible that a touch DNA profile could
have been left behind at a time prior to the alleged incident, it is impor-
tant to gather as much information as possible. What is the item of evi-
dence? Rough objects would be expected to collect more skin cell DNA
as compared to smooth items. Does the item have cracks, crevices, or
grooves where skin cell DNA might collect and be somewhat protected?
An example might be a gun grip, buttons on a cell phone, or a computer
keyboard. Was the item indoors (DNA expected to last longer), or was it
outside exposed to the elements (heat, humidity, water, UV light, and
bacterial growth all degrade DNA)? Was the item an object that may
have been touched by many people (bank door handles, etc.) or only by
very few (a weapon or a car steering wheel, for example)? It is impossible,
however, to put an exact timeline on how long touch DNA evidence, or
any biological evidence for that matter, might last. It is clear that addi-
tional studies are needed in order to help answer the questions regarding
the persistence of touch DNA evidence that are often asked by investi-
gators and attorneys alike.
Is it possible to tell who handled an item last or most?
Due to the variable nature of DNA transfer, it is generally not possible to
determine who might have handled an item last or most. For example,
just because one person’s DNA profile is more prevalent on an item like
a cell phone, does not necessarily mean that they must have handled the
phone last. In addition, it does not mean that the phone must be theirs
because more of their DNA is present. It could simply mean that one of
the factors that tend to increase the amount of DNA transferred (as dis-
cussed above) is in play. In fact, three studies have discussed instances
wherein the person who touched an object transferred someone else’s
DNA to the object.4,10,16
What sort of items might possibly contain touch DNA?
The sky is the limit as almost any item might conceivably contain touch
DNA evidence. The key is to focus on those items that were most likely
to be touched given a particular crime event. In addition, it is important
to select items that have not been handled by multiple individuals as the
DNA results may be uninterpretable due to the complex mixtures of
DNA likely to be obtained. Investigators and analysts must use their
experience and their common sense in order to choose the most useful
and probative items to test for touch DNA.
References can be found online at www.forensicmag.com/
article/touch-dna-analysis-using-literature-help-answer-some-
common-questions.
Suzanna R. Ryan, MS, D-ABC is an owner/consultant with Ryan
Forensic DNA Consulting in Carlsbad, CA. Ms. Ryan is a former DNA
analyst and technical leader with over 13 years of experience in both public and
private DNA laboratories. sryan@ryanforensicdna.com
JUNE I JULY 2012 Forensic Magazine I www.forensicmag.com 33
Item of Evidence Type of case
Firearms, knife handles, weapon handles Any
Fired casing Any
Steering wheel and other vehicle swabs Carjacking, etc.
Fingerprints on victim Any
Ligatures, hand cuffs, shoestrings Strangulation, kidnapping, rape, etc.
Hand swabs from suspects Strangulation, rape
Face swabs from child victims (slapping, hitting) Child abuse
Swabs from limbs removed from animal carcasses Poaching
Cell phone swabs Robbery, etc.
Victim neck swabs Strangulation
Swabs from torn or forcibly removed clothing Rape, assault
Airbag DUI cases and others
Tools Burglary
Baggies Drug possession
Paper demand notes Bank robberies
Clothing items, hats, masks, gloves, glasses Any
Table 2: This is a short list, by no means comprehensive, of some items that may be swabbed and
submitted to the crime lab for touch DNA analysis:
34. To register, learn more
or submit an abstract visit:
ishinews.com
Join more than 800 forensic scientists from around
the globe to explore and discuss the latest research,
technologies and ethical issues in forensic DNA today.
Submit your abstract now!
Oral abstract deadline is June 11th
35. NUCLEIC ACID EXTRACTION
The Maxwell® 16 Forensic System is a compact, plug and play instrument that
extracts high quality DNA from up to 16 samples in about 30 minutes. Optimized
reagents and protocols are backed by service and support, giving you the confidence
to focus on performing and analyzing STR assays.
Promega Corporation
www.promega.com
PCR STRIPS
Each tube of the 8-strip PCR Multiply®-μStrip PCR tubes now features a
molded number for easy identification and tracking, and the connecting
bridges between tubes have been reinforced. The corresponding lid strip
is an optically clear, flat version appropriate for real-time and standard
PCR applications. When used together, the tube and cap strips provide a
leak-resistant seal to minimize sample loss.
Sarstedt, Inc.
www.sarstedt.com
AUTOMATED FT-IR MICROSCOPE
LUMOSisastand-aloneFT-IRmicroscopewithfullautomation.Itisdesignedtocombineperform-
anceforvisibleinspectionandinfraredspectralanalysiswithusercomfort.Duetothemotorization
ofallmoveablecomponentsinsidetheLUMOS,thesystemprovidesahighdegreeofautomation.
Theintuitivesoftwareguidestheoperatorstepbystepthroughtheprocessofdataacquisition.
Bruker Optics
www.brukeroptics.com
AUTOMATED LIQUID HANDLING
The new VERSA™ 10 Automated Liquid Handling Workstation has been developed to
simplifylaboriousroutineprotocolsbycombiningautomatedmulti-channeldispensing(4
or 8 channels), with single-channel, cherry-picking functionality. The customizable sys-
tem set-up, and optional deck modules allow users to automate a range of applications
such as PCR/qPCR plate formatting, sequence reaction set-up, enzymatic modifications,
and general liquid handling.
Aurora Instruments Ltd.
www.aurora-instr.com
JUNE I JULY 2012 www.forensicmag.com I Forensic Magazine 35
DUCTLESS FUME HOOD
The Aura® ductless chemical fume hoods provide advanced safety monitoring and controls.
EverSafe II™ microprocessor safety controller monitors and adjusts fume hood face velocity to
theuserpresetvalue.AurahasbeenASHRAE110testedandprovidescontainmentfromtoxic
fumes and vapors. Aura ductless fume hoods are available in 30, 42, and 54 inch widths.
Mystaire Inc.
www.mystaire.com
36. FINGERPRINT PATTERNSTo comprehend why friction skin is unique, one must look at biological uniqueness
3 MAIN CATEGORIES
ARCHES
Arches are the least
common of the three
general patterns and are
subdivided into two
distinctive groups.
LOOPS
WHORLS
The second most common
of the three general
patterns are Whorls. Whorls
are subdivided into 4 distinct
groups.
Occurs in only 5%
of the population
Occurs in 60-65%
of the population
Occurs in 30-35%
of the population
FREQUENCY OF EACH PRINT TYPE
LOOP TYPE
ULNAR 94% RADIAL 6%
ARCH TYPE
PLAIN 60% TENTED 40%
WHORL TYPE
PLAIN 71% DOUBLE LOOP 13% ACCIDENTAL 3%
CENTRAL POCKET LOOP 13%
PRINT TYPE
ARCHES 5% LOOPS 60-65% WHORLS 30-35%
A L W
TP
U R
ACPLDLP
The most common of the
three general patterns are
Loops. You will see both
right and left loops.
FRICTION RIDGE DEFINED
TTERAATPATTERNSe must look at biolog
of the population
Occurs in only 5%
o comprehend why friction skin is unique, one must look at biological uniqueness
of the population
Occurs in only 5%
of the population
Occurs in 60-65%
of the population
of the population
Occurs in 60-65%
of the population
groups.
are subdiv
s a
are subdivided into 4 distinct
are Whorls. Whorls
of the population
Occurs in 30-35%
of the population
Occurs in 30-35%
FREQUENCY
groups.
OF EACH PRINTFREQUENCY
A
ARCHES 5%
TYPEPRINT
TYPEOF EACH PRINT
L
LOOPS 60-65%
W
WHORLS 30-35%LOOPS 60-65%
WHORL
ULNAR 94%
TYPELOOP
PLAIN 60%
TYPEARCH
PLAIN 71%
TYPEWHORL
U
P
TENTED 40%
P
POCENTRALL
DOUBLE LOOP
6%RADIAL
T
TENTED 40%
CPLDL
13%LOOPOCKETT
3%ALLACCIDENTTA13%DOUBLE LOOP
A
R
FRICTION RIDGE DEFINEDFRICTION RIDGE DEFINEDFRICTION RIDGE DEFINED
37. WHORL TYPES
Plain Whorl
One or more ridges form a
complete circle-like pattern
around the center
*These often look like a
Double Loop Whorl
Two separate loops are present
in one impression
*These often look like the
Central Pocket Loop Whorl
Ridges form a loop pattern which
go around the circle-like pattern
in the center
*These often look like a
Accidental Whorl
A mixture of two different types
of patters
*
LOOP TYPES
Ulnar Loop
side, loop around and exit toward
*These often look like a lake
Radial Loop
Ridges enter from the thumb
side, loop around and exit toward
the thumb
*These often look like a lake
ARCH TYPES
Plain Arch
Ridges enter the impression, rise
in the center, and exit the oppo-
site side of the impression
*
Tented Arch
Ridges enter the impression,
spike upwards in the center,
and exit the opposite side of the
impression
*
SUB CATEGORIES
WHICH PATTERN DO YOU HAVE?
TYPESARCH
TEGSUB CAATTEGORIES
TYPESLOOP TYPES
ArchentedTTe
*
site side of the impression
, and exit the oppoin the center
Ridges enter the impression, rise
ArchPlain
TYPESARCH
site side of the impression
-, and exit the oppo
Ridges enter the impression, rise
Radial Loop
These often look like a lake*
side, loop around and exit toward
Ulnar Loop
TYPESLOOP
Radial Loop
These often look like a lake
side, loop around and exit toward
TYPES
*
impression
and exit the opposite side of the
spike upwards in the center
Ridges enter the impression,
ArchentedTTe
and exit the opposite side of the
,spike upwards in the center
Ridges enter the impression,
These often look like a lake*
the thumb
side, loop around and exit toward
Ridges enter from the thumb
Radial Loop
These often look like a lake
side, loop around and exit toward
Ridges enter from the thumb
Radial Loop
around the center
complete circle-like pattern
One or more ridges form a
Plain Whorl
TYPESWHORL
complete circle-like pattern
One or more ridges form a
TYPES
These often look like the*
in one impression
wo separate loops are presentT
Double Loop Whorl
These often look like a*
around the center
These often look like the
wo separate loops are present
Double Loop Whorl
These often look like a
WHICH TAPPAHICH
39. No, we are not talking about a new state lottery. We are talking about
Lockout/Tagout, the process by which equipment is put into a safe condi-
tion so repairs or maintenance can take place. Forensic crime laboratories
are becoming more automated and complex every year. Sophisticated
equipment such as automated pipetting systems, evidence drying cabi-
nets, fuming chambers, centrifuges, and ultra-low temperature freezers are
commonplace necessities. As our facilities become more efficient and
complex, we must stay alert to the intrinsic dangers.
Although considered necessary mostly in large manufacturing and
production plants, Lockout/Tagout is needed whenever equipment needs
servicing, which is everywhere. Lockout/Tagout measures are taken to
prevent the release of unwanted or stored hazardous energy. Failure to fol-
low good Lockout/Tagout procedures often results in some of the most
gruesome and often fatal accidents encountered in the workplace. Keep
reading to learn how you can design and implement a successful
Lockout/Tagout program for your facility.
When thinking about why Lockout/Tagout is important, one televi-
sion commercial comes to mind. Remember the one where the handy-
man husband has just finished installing a new garbage disposal under the
kitchen sink but dropped something into it. As he is trying to fish it out
with his arm inserted up to the elbow his wife enters the kitchen, goes to
turn on the light and asks which switch to flip. Now, being a capable
electrician and handyman at home, would you want to bet your arm on
which switch to flip?
During the period 1982–1997 NIOSH (National Institute for
Occupational Safety and Health) found that 82% of fatal incidents
involving maintenance or repair to equipment resulted from a failure to
completely isolate or dissipate the energy source.1 In addition, a short four
years between 1992–1996 saw accidents from being caught in machinery
kill almost 750 workers while another 5,000 lost limbs from amputation.2
Sadly, every one of these could have been easily prevented. By imple-
menting a good Lockout/Tagout program you will ensure that your facili-
ty does not experience an ugly accident or worse.
What is Lockout/Tagout?
Lockout/Tagoutisaseriesofstepstakenbyemployeestoisolate,dissipate,or
otherwise prevent unexpected start up or energizing of equipment that
could cause injury. The premise is simple and straightforward; however,
detailed planning and intimate knowledge of the equipment is para-
mount for implementation. For example, say a centrifuge needs servic-
ing. Before the maintenance employee can begin work, he must make
sure the equipment can not be turned on by tripping the circuit breaker
and then placing a lock on the switch so someone else does not ener-
gize the unit while it is being serviced. It may be as simple as pulling the
plug, but many large items are hard-wired and it may not be this simple.
In addition, there may be other dangers, such as stored energy.
Different Types of Hazardous Energy
A good Lockout/Tagout program is exhaustive and meticulously
detailed. Autoclaves, centrifuges, and other automated equipment are
capable of injuring employees in numerous ways. This is because there
are several forms of hazardous energy.
• Electrical energy is most common yet still the cause of many
injuries. Often overlooked are electrical storage devices such as
batteries and capacitors.
• Thermal energy, either high temperature (e.g. steam) or low
(e.g. liquid nitrogen) is also easily recognized. Mechanical work,
chemical reactions, electrical resistance, and radiation can also
produce thermal energy.
• Potential energy is energy stored in pressure vessels (e.g. com-
pressed gas cylinders), hydraulic systems and pneumatic systems,
and mechanical devices (e.g. springs).
• Kinetic energy is associated with moving mechanical parts usu-
ally resulting from the release of potential energy.
Most automated equipment will contain more than one form of
hazardous energy. Thus, a thorough understanding of its operation and
a detailed Lockout/Tagout procedure is needed.
OSHA Requirements
TheOSHAstandardforthecontrolofhazardousenergy,29CFR1910.147,
coversservicingandmaintenanceofmachinesandequipmentwhereacci-
dentalstartuporreleaseofstoredenergycanharmworkers.Itrequires
employerstoestablishaprogramanduseprocedurestolockoutortagout
energysources,andtootherwisedisablemachinesorequipmenttoprevent
injurytoemployees.Thefirststepis to develop a written program docu-
menting the techniques and devices to be used, authorizing personnel,
describing the training, and providing for program evaluation and com-
pliance. Next, identify equipment in your facility that must follow LOTO
and designate them with proper warning signs. Keep in mind that
employers must provide needed Lockout/Tagout devices to trained and
authorized personnel.
Lockout is the placing of a lock to hold an energy isolating device in
JUNE I JULY 2012 Forensic Magazine I www.forensicmag.com 39
Vince McLeod, CIH
Safetyguys
the
Winning with LOTO
40. 40 Forensic Magazine I www.forensicmag.com JUNE I JULY 2012
the safe position. Tagout is the use of a prominent warning device, such as a
tag and a means of attachment, which can be securely fastened to an ener-
gy isolating device. OSHA mandates that lockout take precedence over
tagout. Tagout is only allowed where equipment is not capable of being
locked out. Tags may evoke a false sense of security, and employees must
understand their meaning. Tags are essentially warning devices affixed to
energy isolating devices, and do not provide the physical restraint that is
provided by a lock.
The cardinal rule is “one lock, one key” to prevent inadvertent
removal by another employee. Clearly label each lock with durable tags to
identify the worker assigned to the lock. In general, the worker who installs
a lock is the one who removes it after all work has been completed. The
written program should have procedures on how to deal with maintenance
or service that spans shift changes, special situations, and other absences.
The final check before beginning work is to verify that all energy
sources for the equipment are de-energized. For instance, the employee
should try to start up the equipment and test that all forms of hazardous
energy have been bled down, relieved, disconnected, restrained, and other-
wise rendered safe.
After the maintenance or repair is complete, a reversal of the
Lockout/Tagout procedures will ensure a safe start up. Perform a final
inspection to confirm that all tools and nonessential items have been
removed and that the equipment components are properly installed. Make
sure all affected employees are safely positioned and clear of potential dan-
ger zones. Finally, remove the Lockout/Tagout devices and notify affected
employees of the removal and that start up will commence.
A successful Lockout/Tagout programreliesongoodtraining.Regularly
evaluatetheprogramandcheckthatproperproceduresarebeingfollowed.
Retrainemployeeswhenevertherearechangestojobassignmentsornew
equipmentorenergycontroldevicesareinstalled.Inaddition,ifyouobserve
inadequaciesintheemployees’knowledgeoruseoftheenergycontrolproce-
duresthenretrainingisnecessary.
TheSafetyGuyswelcomeyourcommentsandquestions.Youcane-
mailthemtothesafetyguys@forensicmag.com.Untilnexttime“StayAlert”
andremember“SafetyFirst!”
References
1. “Preventing Worker Deaths from Uncontrolled Release of Electrical,
Mechanical, and Other Types of Hazardous Energy,” National
Institute for Occupational Safety and Health, Center of Disease
Control. Atlanta, GA. NIOSH publication 99-110, August 1999.
http://www.cdc.gov/niosh/docs/99-110/
2. “Worker Fatalities from being Caught in Machinery,” Windau, Janice
A. Compensation and Working Conditions, Winter 1998: 35-38.
3. “The control of hazardous energy,” Occupational Safety and Health
Administration, US Department of Labor. Washington D.C.
29CFR1910.147. May 2011 (http://www.osha.gov/pls/oshaweb/
owadisp.show_document?p_table=STANDARDS&p_id=9804)
Vince McLeodisanAmericanBoardofIndustrialHygieneCertified
IndustrialHygienistandtheseniorIHwiththeUniversityofFlorida’s
EnvironmentalHealthandSafetyDivision.Hehas24yearsofexperienceinall
facetsofoccupationalhealthandsafetyandspecializesinconductingexposure
assessmentsandhealthhazardevaluations.
41. Increasingly more evidence is being collected from
crime scenes. Often by legal mandate, forensic laborato-
ries are required to store more evidence for longer peri-
ods of time, sometimes indefinitely. Other items of
reference, be it weapons or slides, require more and
more room. Space constraints, always one of the major
issues in labs, continue to worsen. What options exist to
better store items that not only provide more storage but
also provide an economy of space? Depending on what
is being stored there are a number of products to help
facilitate that need.
High density storage is one such product that allows
for the more efficient use of space than standard shelv-
ing. Fixed shelving requires a large amount of circula-
tion space to access items. High density storage captures
this lost space by compressing shelving units together.
The shelves are mounted on a rail system with one cir-
culation space. Either manually or with electronic con-
trols, the shelves are moved along the rails to reposition
this circulation space allowing access to the shelf you
need.
The advantage of high density storage is clear; you
can fit far more high density shelves in the same area as
standard fixed shelves. Individual high density shelving
units can be customized for specific needs. Common
forensic examples would be weapons rests or barrel pegs
for a weapons reference collec-
tion or small shelving specifi-
cally sized to store histology
slides.
There are some disadvan-
tages to high density storage.
High density systems are more
expensive than standard
shelves. Because of the com-
pressed nature of the shelves,
only one shelf can be accessed
at a time. This requires coordi-
nation if multiple people want
to access evidence at the same
time in different areas of the
system. There are also special considerations for accom-
modating the rails on which the high density storage
system travels. Because these rails are a few inches high,
adding high density storage to an existing room may
require ramps to access the system. If high density stor-
age is incorporated during new construction or renova-
tion it is important to plan for recessed areas in the
concrete for rail placement.
Another space-saving shelf alternative is vertical
carousel storage. Vertical carousel storage is a computer-
ized system which stores files, books, or anything that is
generally of a uniform size in vertical storage. The sys-
tem assigns each item in storage with an identifier
which allows it to electronically retrieve the item, rotat-
ing the storage unit until the item in question is at the
access port.
The major advantage of vertical carousel storage is
its ability to use the entire floor to ceiling space of its
footprint, greatly increasing the amount of items that
can be stored. This allows any size user to readily access
items stored in the vertical carousel without having to
either stoop or use a ladder. Also of note, because it is a
computerized system, the system can generate a record
of access to the items in storage.
The disadvantages of vertical carousel storage are
similar to that of high density storage. It is more expen-
sive than standard shelving.
It too can create a bottleneck
in accessing evidence, as
only one or two persons can
access the system at once.
Vertical carousel storage is
designed for smaller items
which are of unified size,
such as histology slide con-
tainers, but cannot house
larger items. Because each
item in the carousel has an
identifier, upfront work is
required to label each item in
order to work with the sys-
Answers to Facility Issues
JUNE I JULY 2011 Forensic Magazine I www.forensicmag.com 41
LaboratoryStorage Solutions:
EfficientSolutionstotheEverPresentIssueofStuff
Mostwanted
Susan Halla and Cy Henningsen
Figure 1: High Density Storage
42. tem. Specialized containers may also be necessary in order
to provide a standardized storage size for use within the
system.
Evidence lockers are focused more toward maintain-
ing chain of custody than providing efficient storage space.
However, even evidence lockers can be used more effi-
ciently by the addition of electronic controls. Evidence
storage lockers are generally provided in different sizes and
configurations, some sized for small items such as DNA
kits, some tall and narrow for items such as long arms, and
some larger units for the storage of bulky items. Tradition-
ally a certain number of lockers of each size were specifi-
cally assigned to each investigator. On any given day, an
investigator might have all bulky items from a crime scene
and not have enough lockers of an appropriate size, while
another investigator might not need all of his or her lock-
ers, but there has been no effective way to share space
while providing running proof of chain-of-custody.
Computerized sys-
tems can track which
lockers are in use and
which are open. An
authorized user can
access the computer
system, identify which
locker size they need,
check out an available
locker, and then place
evidence in the avail-
able locker. That lock-
er is then locked and
can only be opened by
that investigator or an
evidence system
administrator. The
system logs all access
to the lockers so that
chain-of-custody can be proven.
Because the computer system controlling the lockers
indicates which lockers are available, there are fewer rea-
sons to permanently assign a certain block of lockers to an
investigator. This can allow a department to get by with
fewer lockers; or support additional staff with the same
number of manually controlled lockers. Additionally, lock-
ers can often be controlled with proximity cards in lieu of
keys, allowing for key cards to be decommissioned easily or
reassigned as staff changes and relieves the issue of losing
valuable keys.
As with the other options presented, additional cost is
one thing to consider when evaluating the introduction of
computer controlled evidence lockers. While electronic
control systems may be
added to existing lock-
ers, power and storage
for the control system
components is required
for installation and
would be an additional
cost either as a retrofit
or in new construction.
As Benjamin
Franklin noted, “…in
this world nothing can
be said to be certain,
except death and taxes.”
Appending this quote to
add “storage” seems
appropriate to the way
in which forensic facili-
ties must operate. It is
assured that storage
requirements will con-
tinue to grow and finding smart ways to manage storage by
more efficiently and effectively using the space available is
a necessity.
Susan Halla (susanh@crimelabdesign.com) is a
Project Leader and Senior Forensic Planner with Crime
Lab Design which provides full architectural and
engineering services for forensic and medical examiner
facilities worldwide.
Cy Henningsen (cyh@crimelabdesign.com) is
an Equipment Coordinator with Crime Lab Design.
www.crimelabdesign.com
42 Forensic Magazine I www.forensicmag.com JUNE I JULY 2011
Figure 2: Inside an evidence locker
Figure 3: Run of evidence lockers
Figure 4: Vertical Carousel Storage
