1. Blood stain pattern analysis is an important tool in crime scene investigation and reconstruction. It involves analyzing the shapes, locations, and distributions of bloodstains to interpret the physical events that caused them, using principles of biology, physics, and mathematics. 2. Blood stain pattern analysis can help determine what events could have occurred at a crime scene as well as what events could not have occurred. The analysis of the origin, direction, and force of bloodstains found at a crime scene provides clues about the crime. 3. There are three main types of bloodstains: passive stains caused by gravity, projected stains caused by external forces on the blood source, and transfer stains caused by contact between