As DNA Evidence Piles Up, Sheriff Expands His Crime Lab

Wednesday, Oct. 3, 2007 | Faced with a swelling demand for DNA-based forensics analysis, the San Diego County Sheriff’s Department is developing a rapid response DNA team that, when fully deployed, will almost double the department’s capabilities.

The new team, which will consist of 10 analysts, will focus primarily on street crimes including burglaries, robberies and auto thefts, and aims to cut the time it takes for DNA analysis from several months to about two weeks.

Traditionally, the sheriff’s DNA forensics analysts have spent the bulk of their time poring over evidence in homicides and sexual assault cases, but the expansion of the team will allow the department to branch out, making the most of their increasing awareness of the far-reaching power of DNA as evidence.

“It’s going to have a tremendously positive impact on us and on all the investigative units that they do analysis for,” said Lt. Dennis Brugos of the Sheriff’s homicide detail.

“Pretty much every case we’re involved in involves some type of DNA analysis,” he added.

The sheriff’s crime lab, which also serves all the other police departments in San Diego apart from the San Diego Police Department, first started analyzing evidence and crime scenes for traces of DNA in 1999. Today there are 12 analysts working on DNA at the crime lab.

Steve Guroff, a supervising criminalist for the department, said in the early days he and his seven-person team were primarily focused on working on the two crimes most often associated with DNA evidence: Murders and rapes.

The first few years of DNA gathering were relatively unsophisticated, Guroff said. Most DNA samples came from blood or semen left at the crime scene, he said, and detectives and forensics experts were therefore quite limited in the scope of crimes they could investigate with their revolutionary techniques.

Today, however, experts are able to extract samples from a far wider range of physical evidence, including chewing gum, strands of hair, clothing and even simply surfaces the criminal has touched with bare skin. As a result, the sheriff’s crime lab has found itself swamped with cigarette butts, soda cans and bodily fluids, all vying for attention from the men and women in white coats.

And since the passing of Proposition 69 in 2004, which authorized and expanded the collection and use of criminals’ DNA samples in California, the state has been compiling an enormous DNA database from felons. That database is now the third largest in the world, Guroff said.

Analysts at the sheriff’s crime lab now have the ability to run DNA samples they find at crime scenes through the database to look for matches, a technique that has revolutionized their work, Guroff said.

As DNA evidence collection has matured as a science, the Sheriff’s Department has found itself at a critical juncture, said Gregory Thompson, the department’s director of forensic services. It has the ability to get DNA from smaller and smaller samples, and a new legal route offered by the state’s DNA database.

“By putting this team into place, we’re taking advantage of that crossroads,” Thompson said.

The DNA phenomenon has also extended to cold cases, hundreds of which have been reopened by the sheriff’s department in the light of the advances in evidence analysis. That’s only increased the pressure on the crime lab.

From 2005 to 2006, the department’s demand for DNA analysis increased by 40 percent, Thompson said. From 2006 to 2007, that demand increased another 50 percent.

“This beleaguered crew of criminalists is looking at this just exponential increase in their workload,” Thompson said.

The increased demand isn’t going away, Thompson said. As law enforcement officers become more aware of the power of DNA analysis and become more adept at using DNA collection methods at their crime scenes, the crime lab is going to see evidence continue to pile in.

Because of the increased workload, turnaround times for DNA analysis at the lab have slipped in the last few years.

Thompson estimated that often it can currently take between 90 and 120 days to analyze evidence collected at crime scenes in the county. As homicides and other serious crimes occur, other less serious crimes are pushed to the end of the line for analysis, causing an ever-present backlog of cases.

The introduction of the sheriff’s new team of analysts aims to bring that turnaround time for analysis in the street crimes — robbery, burglary and auto theft — down to no more than 15 days, Thompson said.

By creating a team that focuses exclusively on day-to-day property crimes, Thompson said, other analysts will be free to work on the violent crime scenes, which he said often take months for an expert to fully canvass.

The crime lab’s request for the new team was approved in this year’s county budget. Thompson said it will cost the county approximately $1.2 million, and that he is in the process of recruiting members for the new team. It should be operational by January 2008, he said.

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