National Forensic Science Week takes place Sept. 20 to 26 to recognize the work done in crime labs across the country to solve cases.
Locally, that important part of the criminal justice system is handled by the Bexar County Criminal Investigation Laboratory, which processes evidence in nearly 9,000 local crime cases a year.
A staff of 30 at the lab in a typical year will work on more than 700 firearm and gunshot primer residue cases, 1,000 cases involving DNA, and more than 7,000 controlled substance cases, according to Orin Dym, the director of the lab located in the Medical Center.
"It’s a pretty busy operation with controlled substances or drug cases really being the major portion, which is rather typical of a crime laboratory," Dym said.
Dym says 90% of their workload comes from the San Antonio Police Department and Bexar County Sheriff’s Office, and the rest from smaller suburban police departments.
The lab was established in 1985, and the first in the state to use forensic DNA analysis to investigate crimes in 1989. It also became world renowned for an automated system to examine gunshot primer residue in the 1990s.
Crime Scene Investigation, or CSI, shows have proven to be popular on network television, cable and most recently Netflix.
The shows often solve crimes in an hour of T.V. time.
But Dym said crime labs are only a part of criminal investigation in the real world.
"You have to remember, we are here to examine physical evidence related to possible crimes, so we are a tool in the toolbelt of investigators, we're a piece of that puzzle, " he said. "We're something they can use."
And he said there are cases where they can offer little to no help.
"If there were a crime where there was a lack of physical evidence, that's not something we are aware of," Dym said.
He said DNA analysis continues to play a major role in crime investigations.
"We've seen advances in DNA in particular, where we're able to work with smaller sample sizes, where we're able to get more answers when we have the power of that DNA database, you know, where year's later someone appears we're able to make a match," said Dym.
The FBI operates the Federal DNA Database Unit or FDDU.