While I was visiting the Central Coast Chapter of Sisters in Crime, the speaker, a criminologist, shared many interesting tidbits.
Among them were a few facts about fingerprints.
Latent fingerprints are collected from all over. The computer helps match fingerprints. Using both the state and federal system, sometimes will come up with a match in about two minutes. The latest FBI system will check against all fingerprints in the system. Of course, the fingerprints must be in the system.
State law prohibits including the fingerprints of teachers and others who have had to be fingerprinted for their job.
There are very few true stranger murders. The killer is usually someone the victim knows.
But--there are around 200 active serial killers in the United States now. Serial killers usually stalk their victims.
Profiling isn't always a good thing. Knee jerk reactions are almost always bad.
Surveillance cameras are everywhere.The average American is video taped 18 times a day. In England, it's 100 times a day.
The statute of limitations for an assault is three months.
Burglars almost always leave blood behind which means DNA.
Evidence in a murder is kept forever.
DNA is now collected of any person with a misdemeanor or felony. DNA is just another tool.
There is a 10 year statute of limitations on a rape case and 6 years for a felony.
The TV show CSI has created problems for prosecutors.
In order to obtain fresh DNA from a suspect, he may be followed around until he throws away a cup he's been drinking from. It is legal for the investigator to retrieve the cup from the trash.
The speaker had many other interesting facts, but keep in mind this was all about San Luis Obispo county (which is fortunate in having modern equipment) which is in the state of California.
Anyone who is a fan of my Rocky Bluff P.D. series, knows that my fictional town is poor and the police department doesn't have much in the way of modern equipment and has to send evidence to the lab in Ventura. My main reason for doing this is because I want my police detectives to mainly solve crimes the old fashioned way through asking lot of questions, paying attention to people's reactions, and following the clues.
My Deputy Tempe Crabtree series, is set in Tulare County. She doesn't have access to as many wonderful law enforcement tools. It's a lot more fun to write that way.