Using DNA in nonviolent offenses would swamp crime labs

In the future, as the national CODIS database expands to include, conceivably, every US arrestee, DNA will be used to solve all sorts of common crimes, not just violent offenses. It can be used for nonviolent crimes now, in fact, but the main barrier to doing so is a lack of resources at crime labs. In Northwestern Louisiana, federal grants are being used to process DNA in burglaries in a pilot program, reports the Shreveport Times.

The effort to clear a backlog of burglary cases started in March. The crime lab was staffed with eight new full-time DNA analysts and the will to go after a stack of property crimes cases, crime lab Director Jimmy Barnhill said.


The crime lab has tested DNA from 76 cases this year — 70 burglaries, five sexual assaults and one classified as "other."

Of those 76 cases, 78.5 percent came back with DNA matching someone in the Combined DNA Index System maintained by the state, crime lab forensic DNA analyst Jessica Esparza said.

Burglaries had an 84 percent hit rate against CDIS, meaning 84 percent of the time an unknown burglary suspect will be named by the system, Esparza said. She said 59 percent of the total 2011 hits came from the Shreveport Police Department and 6 percent came from the Bossier City Police Department.

As new techniques come online like "touch DNA" that let investigators discover biological evidence in settings heretofore considered clean, the possible forensic uses for such technology will continue to grow faster than will the number of techs employed by the state to process the evidence, and much faster than city and county budgets to pay for local or private processing. There are opportunities for privatization here, but private labs doing this work also face greater responsibility to back it up in the courts than ever before when their work is used later on.

Either way, ramping up lab volumes while doing the work the right way, in a manner that will survive appellate and regulatory scrutiny, is one of the major challenges facing modern crime labs. They could begin processing DNA in more burglary cases, but as it stands, doing so requires a tradeoff with, say, reducing rape-kit backlogs. Short of some special, federally funded pilot program like in Shreveport, I doubt most law enforcement agencies would choose of their own accord to prioritize DNA testing resources on nonviolent offenses while untested rape kits linger on their storage shelves.

The 82nd Texas Legislature passed a bill this year that will require the creation of statewide rules at DPS governing collection and preservation of biological evidence. That's pretty much where the rubber meets the road on whether local labs and evidence handlers can competently manage the ever-growing volume of biological evidence coming their way. If it needn't be properly stored, cataloged, etc., they can probably go along to get along. If the evidence must be managed using high professional standards, the cost of expanding DNA testing to new domains may be, as a general rule, too prohibitive. At a minimum that tension will be explored more thoroughly as those rules are developed, both at DPS and perhaps on this blog.

RELATED: From Forbes, "Is DNA testing of dog poop forensic science gone too far?"

See related Grits posts: 

• Senate bills encourage retention, testing of old DNA evidence
• DNA could solve burlgaries if crime labs were bigger, better, more trustworthy 
• 'The DNA's over there, right next to the jelly: The problems with the preservation of evidence in Texas'
• Backlog of DNA cases complicates Houston crime lab's bias problems
• Large backlogs for DPS forensics testing
• Unanalyzed evidence held by law enforcement agencies
• Test possible innocence cases among Bexar DNA cache
• The coming fight over independent crime labs