The focus of our presentation is the preservation of DNA evidence and its use for capital postconviction appeals. We will consider both the scientific and legal factors that effect the ability to use DNA testing postconviction. First half of our presentation will consider some of the science and technology considerations behind preservation of DNA evidence. While in the second half the presentation Joan will explore the Law and postconviction DNA testing
Overview of presentation: The key issues to the preservation of DNA testing are listed here. Collection – some of the questions that must be asked are: what happened at the crime scene, were the responding officers properly trained in the collection of biological evidence? Did they collect enough? Were control samples collected? Documentation – was adequate documentation made of the collected evidence; is there a chain of control. Packaging – how was the evidence package at the crime scene – paper/plastic dilemma, contamination Preservation and Storage – at the forensic lab, other evidence storage facility Law/protocols - what happens to evidence after conviction - what is the law, will a sample be preserved to allow postconviction testing
This shows the time line of how quickly the science of DNA testing has developed.
Lets us first turn to what is key to the preservation of DNA evidence. DNA is stable and has been found in Egyptian mummies and Wooly mammoths. This illustrate 2 extremes that are used for the preservation of DNA - low humidity (dry samples) and freezing.
Prior to the availability of DNA testing, most biological materials that were collected were those that could be tested for blood type, fingerprints, etc. The collection and storage methods would have varied depending on the anticipated test. For example, blood typing requires liquid blood to be obtained and stored in a tube with anticoagulant, and refrigerated as soon as possible. This is not nearly as lasting or viable a long-term storage method for DNA testing as drying a few drops of blood on some blotting paper. For example as used by the Armed Forces DNA Registry (Military DNA “Dog Tags”)and proven to preserve evidence in a NIST study. Even since the advent of DNA, different sources may require different storage. For liquid blood – anticoagulant and refrigeration is required. The minimum usable sample size varies by material type; a semen stain, the size of a dime; blood stain, the size of a quarter. Fifteen hairs with follicles intact are needed. A frequent question is what is the effect of storage temperature and humidity on evidence samples?
A frequent questions is: do samples have to be refrigerated or frozen to be preserved? There are varying opinions on this in the legal literature. Where do we find information about the preservation of DNA evidence? One source is the scientific literature Samples were all dried blood, that had been dried on paper. National Institute of Standards and Technology (Gaithersburg MD and Boulder Co) is the top national scientific laboratory for measurement standards. They keep atomic time and the standard length of a meter, their standards are used to calibrate the scales in the supermarket and the pump at the gas station. They make certified standard reference materials to be used in scientific measurements. Their laboratories use the latest and most accurate methods available. NIST has been funded by the National Institute of Justice to improve forensic DNA testing methods. There are 2 NIST laboratories that work in with standards for forensics - Electronics and Electrical Engineering Laboratory’s Office of law enforcement Standards and Chemical Science and technology laboratory, DNA Technologies Group, Human Identity project . Both do Research in Deoxyribonucleic Acid (DNA) Identification Methods and Standards Five major research areas : •Develop new DNA tests that are more rapid and efficient than those currently used. • Evaluate and develop technologies to aid forensic DNA typing. • Develop DNA standards so that laboratories around the world may reliably compare their results. • Conduct tests of laboratories around the world to insure accurate results in DNA testing. • Create useful information databases (STRBase)
The size of sample needed has decreased from the size of a quarter for RFLP to the theoretical limit of one cell for PCR/STR But a lot of factors can alter the efficiency of the PCR reaction. TOF mass spectrometry reported to be more accurate than the currently used capillary electrophoresis When seeking testing always consult a laboratory for
To be preserved samples must be dried. This is why the policy is not to use plastic bags for crime scene collection. Once at the laboratory, and samples are dried plastic may be used.
Source: Gianelli & Edward Imwinkelried, Scientific Evidence 106-107 (1986). Is this Illinois?
While the U.S. Supreme Court has rejected a federal constitutional duty to preserve biological evidence for DNA testing in crimes, some state and local jurisdictions have recognized such a responsibility. Lt. Michael O’Connor of the cold case squad at the Pima County Sheriff’s Office recently said at one of the Criminal Justice Luncheons: If it’s a non-homicide case, they keep the evidence for maybe 10 years. If it’s a case involving a homicide, they keep the evidence “forever.”
More than 60 people have been exonerated on DNA evidence in the United States, including 14 capital defendants. Cases of exoneration (freed after conviction on finding of innocence) due to DNA evidence are manifold and hopefully will someday overtake the number of persons whose names were cleared too late. For example, while 12 people have been released from Illinois’ death row since DNA exonerated them, as many have been executed since capital punishment was reintroduced in that state in 1977. This was just one among many factors that led the former Gov. Ryan to place a moratorium on the death penalty in that state until the fairness of its application and sufficiency of procedural safeguards could be studied. Chris Ochoa – Convicted of the 1988 murder of Nancy DePriest, an Austin, Texas, Pizza Hut employee, he was released in 2001 after serving 12 years on Texas’ death row. He went on to graduate from the University of Texas and now is a law student at the University of Wisconsin-Madison, the school whose innocence project helped lead to his freedom. Earl Washington, Jr. – convicted of murder of a Virginia woman he was released in 2001 after serving nine years on Virginia’s death row (in 1985 he came within nine days of being executed). Ray Krone – convicted in 1992 of the murder of Kim Ancona, a Phoenix bar waitress, he was released from Arizona’s Death Row April 29, 2002 (the 100th U.S. exoneree) after DNA evidence ruled him out and pointed to another man, Kenneth Philips, who was then serving a prison term for sexual assault and was due out in July 2002. Kirk Bloodsworth – The first person to be exonerated from death row due to postconviction DNA testing, according to the Benjamin Cardozo School of Law Innocence Project. He was convicted in March 1985 of rape and murder of a 9-year-old girl. He appealed and his conviction was overturned, he was retried and convicted and sentenced to two life terms. He was released in June 1993 after spending eight years in prison, two of them facing execution, after PCR testing of the victim’s underwear excluded him. He is the namesake of a bill currently winding its way through Congress, called the Advancing Justice Through DNA Technology Act, which includes the Innocence Protection Act, designed to help states pay for postconviction DNA testing.
DNA in Capital Punishment (Death Penalty Eligible) Cases
Preservation of DNA Evidence and Capital Postconviction Appeals Jackie Nicol and Joan Bundy
Preservation of DNA Evidence for Postconviction Testing <ul><li>The Issues: </li></ul><ul><li>• Collection </li></ul><ul><li>• Documentation </li></ul><ul><li>• Packaging </li></ul><ul><li>• Preservation and storage </li></ul><ul><li>• Laws/protocols for keeping evidence after conviction </li></ul>
Brief History of Forensic DNA Typing <ul><li>• 1900 – First useful marker system – ABO blood groups </li></ul><ul><li>• 1953 – Discovery of the structure of DNA </li></ul><ul><li>• 1960 – Some 17 or so inherited blood typing systems </li></ul><ul><li>• 1980 – White describes first polymorphic RFLP marker </li></ul><ul><li>• 1985 – Jeffreys et al. discovers multilocus VNTR probes and uses them to exonerate suspect in 2 rape-homicides </li></ul><ul><li>• 1985 – First scientific paper on PCR </li></ul><ul><li>• 1986 – First use of PCR-based typing in forensics </li></ul><ul><li>• 1988 – FBI starts DNA typing </li></ul><ul><li>• 1991 – First scientific paper on STR typing </li></ul><ul><li>• 1993 – Kirk Bloodsworth, the first person exonerated from death row due to postconviction DNA testing </li></ul><ul><li>• 1998 – FBI launches CODIS database </li></ul><ul><li>• 2004 – At least 14 persons exonerated by DNA evidence </li></ul>
DNA is remarkably stable It has been identified in: Egyptian mummies! Wooly mammoths!
Yet DNA is not always so well preserved. <ul><li>So what impacts preservation and usability? </li></ul><ul><li>• How and why biological material is collected (DNA testing, fingerprinting, serology, etc.) </li></ul><ul><li>• Moisture level </li></ul><ul><li>• Light level/type </li></ul><ul><li>• Impurities (mold, pollen, dirt, bacteria, etc.) </li></ul><ul><li>• Storage temperature </li></ul><ul><li>• Storage media (paper/plastic dilemma) </li></ul><ul><li>• Amount of evidence collected </li></ul><ul><li>• Sample size available (is one cell enough?) </li></ul>
NIST Study on the Effects of Storage Temperature and Humidity <ul><li>Field Samples (318 samples): </li></ul><ul><ul><li>From state health labs, stored from 2 to 15 yrs </li></ul></ul><ul><ul><li>Most stored at ambient warehouse temperatures, one set at -20 ◦ C for 6 yrs </li></ul></ul><ul><ul><li>Dried and sealed??? – conditions not known (paper/plastic?) </li></ul></ul><ul><li>4 Control Samples (6 of each sample): </li></ul><ul><ul><li>NIST prepared, stored for 7.5 yrs </li></ul></ul><ul><ul><li>Dried in vacuum desiccator, sealed in tubes </li></ul></ul><ul><ul><li>-198 ◦ C, -80 ◦ C, -20 ◦ C and lab ambient </li></ul></ul>
Results of NIST Study <ul><li>• Typeable DNA was recovered from all samples in all studies </li></ul><ul><li>• Some loss of larger loci seen in oldest (15yr) field samples </li></ul><ul><li>• Samples stored at ≤ -20 ◦ C have intact high molecular weight DNA; ambient samples show signs of degradation </li></ul><ul><li>• Mitochondrial DNA was amplified from all storage media types </li></ul><ul><ul><li>If humidity is controlled, temperature is not the key to preservation </li></ul></ul>
Technology Advances and Postconviction DNA Testing <ul><li>Improved methods have allowed analysis of samples once thought too small </li></ul><ul><ul><li>RFLP vs. PCR/STR </li></ul></ul><ul><ul><li>TOF-Mass Spectrometry is more accurate that current Capillary Electrophoresis </li></ul></ul><ul><li>Extraction techniques </li></ul><ul><ul><li>Important for determining the quality of DNA extracted. </li></ul></ul><ul><li>Human Y-Chromosome Markers </li></ul>
Keys to Optimal Preservation and Forensic Utility <ul><li>Evidence must be properly: </li></ul><ul><li>Documented </li></ul><ul><li>Collected </li></ul><ul><li>Packaged </li></ul><ul><li>Preserved and </li></ul><ul><li>Tested </li></ul><ul><li>To meet both the legal and scientific requirements for admissibility in court </li></ul>
Preservation Case Law <ul><li>• Brady v. Maryland , 373 U.S. 83 (1963) —prosecutor must disclose material that is exculpatory to the accused </li></ul><ul><li>• State v. Bryant , 439 F.2d 642 (D.C. Cir. 1971) — duty to disclose cannot be avoided by destroying (or failing to collect) evidence </li></ul><ul><li>• State v. Wright , 557 P.2d 1 (Wash. 1976) —failure to preserve murder victim’s clothing violated defendant’s due process rights </li></ul>
Legal Doctrine on Preservation <ul><li>Factors in assessing whether failure to collect, loss or destruction of evidence worked a deprivation of due process: </li></ul><ul><li>(1) Likelihood that lost evidence would have been exculpatory; </li></ul><ul><li>(2) Likelihood that defendant was significantly prejudiced at trial by lack of evidence; </li></ul><ul><li>(3) Level of government culpability for the loss </li></ul>
Legal Preservation Requirements <ul><li>• States vary widely: In terms of how long—or even whether—they require preservation of DNA evidence. Key determinant: Where they fall on the finality vs. fairness spectrum. </li></ul><ul><li>• Arizona: Requires material kept u ntil all judicial proceedings have ended or, for blood, 35+ years </li></ul><ul><li>• CA, MI, NE, NC, OK, TX : Through incarceration </li></ul><ul><li>• Florida: Probably the shortest, at two years after final judgment or, for capital cases, 60 days after execution of sentence (or of the person? not clear) </li></ul><ul><li>• Colorado: N o law enforcement duty to preserve or liability for failure to preserve DNA! </li></ul>
AZ Postconviction DNA Testing <ul><li>Requirements: </li></ul><ul><li>(1) Defendant convicted of and sentenced for a felony offense </li></ul><ul><li>(2) Evidence still in the possession of the state or a lab </li></ul><ul><li>(3) Evidence quantity and quality sufficient for scientific DNA testing </li></ul><ul><li>(4) Evidence has not previously been subject to DNA testing or test desired was not in existence at time of original/prior testing(s) and can resolve an issue not resolvable by the previous test(s) </li></ul><ul><li>(5) Reasonable probability that defendant would not have been prosecuted or convicted if exculpatory results had been obtained through DNA testing—court must order testing </li></ul><ul><li>(6) Reasonable probability that defendant’s verdict or sentence would have been (merely) more favorable had DNA testing been available at trial, or DNA testing will produce exculpatory evidence (but ∆ likely would still be convicted of some lesser crime)—court may order testing </li></ul>
DNA Testing in Capital Cases <ul><li>The 10% rule: </li></ul><ul><li>• Only about 10% of all death-row appeals have viable DNA component (either no DNA evidence collected or preserved or no ID/actual innocence) </li></ul><ul><li>• Only 14 of 115 U.S. exonerations so far due in part to DNA testing (~12%) </li></ul>
The Lucky Ones Chris Ochoa Earl Washington Jr. Kirk Bloodsworth Ray Krone