The story is straight out of Nancy Drew: A half-eaten corn dog found at the scene of a suburban office burglary yields DNA that links the crime to a man with 27 previous arrests. It's not fiction, though; it happened in Hennepin County, Minn., earlier this year.

New research shows that using DNA to solve property crimes like burglaries -- and not just violent crimes like homicides and sexual assaults -- is particularly effective. Last month, the Urban Institute's Justice Policy Center released a study that found that DNA evidence from property crime scenes identifies suspects in twice as many cases and leads to twice as many arrests as more typical tools like witnesses and fingerprints.

But in the report, "The DNA Field Experiment," researchers also wrote that if collecting and processing DNA evidence at property crimes became the norm nationwide, it would overwhelm the criminal justice system.

"Most jurisdictions are having trouble processing special assaults and homicides," let alone burglaries, said John Roman, the study's principal author.

The latter finding is particularly relevant to local law enforcement officials. Because of limited forensic resources, the practice is working its way into police custom slowly.

"It's a new thing to this area," said Sgt. Kevin Gasiorowski, who heads the Pittsburgh police burglary squad.

He said it is unrealistic to expect Allegheny County's crime lab to handle the glut of evidence that would result from collecting DNA at all property crimes.

"We have 3,000 burglaries a year. They would be overrun," said Sgt. Gasiorowski. "It's not like on TV where you just get a swab of something and two minutes later it pops up on a computer."

Even excluding property crimes, competition for forensic resources is tough.

"You've got people saying you've got to look at old cases, you have the people who are investigating crimes, you have the people who are prosecuting crimes, and we're all taxing a system that has finite capacity," said John Rago, founding director of the Cyril H. Wecht Institute of Forensic Science and Law at Duquesne University.

"We always deal with a backlog as it is," said Fred Fochtman, director of laboratories at the Allegheny County medical examiner's office, which handles DNA evidence for the city police department. On average, the lab processes samples with a one-year delay.

Violent crimes are processed first, but Dr. Fochtman hopes his lab will be able to take on more property crimes when the backlog decreases, which he believes will happen in the next year due to grant funding from the National Institute of Justice and an increased use of robotics that automate some DNA testing.

The lab recently changed its standards for processing evidence, said DNA analyst Janine Jeglinski.

It now accepts material submitted without a "reference sample" from a suspect, which is then compared with the DNA from the scene, and evidence from property crimes has been submitted with increasing regularity. If the lab tests these unknowns and uploads them to CODIS -- an FBI database containing DNA profiles of missing persons and convicted offenders -- analysts can and often will find a match.

"We realized a lot of these burglaries and robberies are committed by repeat offenders," said Ms. Jeglinski. The extent to which police can rely on DNA evidence to solve property crimes depends on the time and money they have to dedicate to lower-priority cases.

"What do you do for the guy who lives in Rosslyn Farms and his car is stolen?" said Mr. Rago. "Do you send that in for DNA testing?"

"Different communities value burglaries differently," said Mr. Roman.

In affluent Orange County, Calif., one of the five communities that participated in the Urban Institute's study, more than 70 percent of the forensic case load is from property crimes, said Dean Gialamas, who directs the crime lab there in addition to serving as president-elect of the American Society of Crime Laboratory Directors.

"I truly believe as a scientist that the more property crimes we can test, the more we're going to be able to lower our crime rate in general," said Dr. Gialamas, citing the inevitable interconnectedness of violent and nonviolent crimes. "Major criminals didn't start with rapes and murders, they started with petty crimes like shoplifting and burglary."

In one Orange County case, a DNA sample from a burglary ended up solving three additional burglaries -- and one homicide.

This type of breakthrough is one reason the authors of the Urban Institute report are pursuing a second study to determine if processing DNA evidence from property crimes will eventually save money, despite the initial cost.

"The big hurdle is that you have to have the laboratory capacity," said Mr. Roman.

Mr. Rago said there would need to be a public policy commitment on the part of local, state and federal governments to overcome the budget constrictions crime labs face.

"Society is pushing us," he said.

After all, he pointed out, juries have come to expect DNA evidence in every case.

First Published: July 7, 2008, 4:00 a.m.