What is a crime scene? It is not just a scenario from of "CSI" on television, but a puzzle many forensic specialists try to solve and eventually reconstruct upon the crime itself.
Maintaining his strategy since last semester of continuing education for professionals, Dr. Dwight Adams, UCO forensic director, in cooperation with Oklahoma State Bureau of Investigation lunched a workshop for bloodstain pattern analysis.
Organized to train forensic scientists in recognizing and interpreting bloodstains at crime scenes, the workshop took place in the NUC from Jan. 8 through 12.
"This class has individuals who were both new to forensic science, as well as those who have been there for years and served as a refreshing course," Dr. Adams said.
Using real human blood to conduct his experiments, Capt. Tom Bevel tested various ways of creating bloodstains. The experiments included impact angle stains; 90-degree angle drops with mathematical calculations to identify where the stain originated from; and cast of stains resembling blood coming from a murder weapon. Bevel said such testing could identify if the murder is left or right handed, distance and exclude types of possible murder weapons.
Retired after 27 years with Oklahoma City Police Departments, Bevel explained the difference of bloodstains based upon impact velocity. Three basic patterns are used as general comparison. Passive stains formed after gravity acting as the only force on the blood such as drops from a wound. Projected stains are spreads caused by a gunshot or impact on the body after it hit the ground. Contact stains are left due to blood from the murder weapon.
"In the shooting experiment we were able to identify that the misty blood is a come back pattern from no more than four feet," Bevel said. He said the importance of such experiments is to verify if someone was a shooter or in close proximity with the victim at the time of the crime.
According to Bevel, crimes do not happen in ideal lab conditions and blood is almost never on a white surface but clothing or other hard-to-distinguish blood on surface.
"Whoever is a suspect we treat his clothes under proper lighting, and after DNA test we can verify testimonies," Bevel said.
After processing all experiments, the forensic scientists collect the data and draw conclusions about the different crime scenes and possible types of suspects.
Jolene Russell said learning the different ways of how bloodstains occur helped her in her career as OSBI crime scene investigator. She said she took the same course over 10 years ago.
Be the first to comment on this article!