In a recent episode of Castle, a young man is on death row, about to be executed, and Alex, having interned with an attorney on the man’s case, believes the inmate to be wrongly convicted, and requests Castle’s help in righting this wrong.
He heard the screams from across the street. Dropping his towel, he hurried next door to his neighbor’s house only to discover her unresponsive on the floor. Under the low lights, he reached down and touched her neck, seeking a pulse. Nothing.
Removing his hand, he then felt the stickiness on his fingers, which he tried to wipe away. Then he saw it: a slow pool of blood starting to form under her. Now, staring down at it, all that he thought about was getting out of there, before the police arrived, before someone became suspicious and noticed that a crime had taken place.
It was too late, as patrolmen arrived and arrested him.
– Part of the story from Castle, episode 607, Like Father, Like Daughter
This episode got me thinking about forensic science and its role in crime solving.
During my time at the Citizen’s Police Academy, we had a session on the Forensics Unit, where we discussed Locard’s Exchange Principle. Dr. Locard believed that “…no matter where a criminal goes or what a criminal does, by coming into contact with things, a criminal can leave all sorts of evidence, including DNA, fingerprints, footprints, hair, skin cells, blood, bodily fluids, pieces of clothing, fibers and more. At the same time, they will also take something away from the scene with them.” See Forensic Handbook
When the first officer arrives on the scene, so begins the chain of custody, and also the crime scene log. The log and notes include such details as the fact of if the lights were on or off, when officers arrived; the temperature of the air, as well as if any dust is disturbed.
While many criminals may feel that a perfect murder is possible, it isn’t. The advance of technology, along with a statute of limitations that doesn’t expire, makes it possible for a criminal to be caught even 20 years after the murder. From popular shows, like CSI, many feel that a little bit of bleach will make a crime scene disappear, but according to the forensic experts, it might degrade the DNA, but not the blood. Blood will still react under Luminol, and this can indeed help to build a criminal case, even if the human remains are not recovered (yes, there have been successful criminal prosecutions done when a body has not been found).
Facebook and if you are in the Richmond area, please mark your calendars and join her at Regency Square Mall on December 21st at 12 p.m.