The rising domestication of DNA evidence
Once reserved for the worst crimes, DNA tests increasingly used in relatively mundane property cases.
DENVER - The burglar was undone by his taste for strawberry soda.
RazJohn Smyer, a suspect in a string of Denver-area break-ins, often checked his victims' refrigerators and helped himself to a drink. The soda cans he left behind gave police enough DNA evidence to link him to five burglaries. He is now serving a 20-year sentence.
Smyer's conviction is just one example of how DNA evidence is increasingly being used to solve everyday property crimes across the nation. Once reserved mostly for violent cases such as rape and murder, genetic testing is now much cheaper and faster than when the technology was new.
"Regular watchers of
may be led to believe that this technology is already being used in this way, but it's really brand new," said John Roman of the Urban Institute, lead author of a study on the issue. "This really is the start of a revolution in policing."
The evidence can include almost any biological material left at a crime scene: saliva taken from food, skin cells from the steering wheel of a stolen car, drops of blood from a thief who got cut on a window pane.
By using DNA, authorities are five times more likely to identify a suspect than with fingerprints alone. DNA also doubles the number of suspects who are identified, arrested and prosecuted, according to the study, which was funded by the National Institute of Justice.
Burglars identified with DNA evidence in Denver usually plead guilty because prosecutors "have very solid evidence," Denver District Attorney Mitch Morrissey said.
For many years, the high cost of DNA tests and the long wait for results made it difficult for authorities to use the technology in property crimes. But genetic testing has come a long way since 1989, when investigators needed a blood sample about the size of a half dollar or a seminal-fluid stain the size of a dime to perform an accurate analysis, which took about 10 weeks and cost $1,000.
"It was great for the prosecution, but it wasn't good for the investigation," said Paul Ferrara, retired director of Virginia's state crime lab who developed the nation's first DNA data bank. "My only surprise today is that it's been this long in coming."
Analysis on some cases now takes as little as 12 hours and costs only about $50.
Police in New York City and Chicago use DNA testing routinely. Other agencies, such as the Los Angeles Police Department, still reserve it for the most serious crimes. Police in Britain began using DNA for property crimes in 2001.
In Denver, detectives linked a suspect to five burglaries after he left saliva on a piece of "gold coin" candy. The man, who was on parole when he committed the burglaries, is now serving a 48-year sentence. Another thief was arrested after detectives found his DNA on a tuna sandwich. In a different case, investigators were even able to extract DNA from part of a lollipop left at a crime scene.
Once genetic material is analyzed, a profile is developed and compared with state databases or entered into the FBI's Combined DNA Index System, which contains six million offender profiles and more than 225,000 pieces of evidence awaiting a match.
The National Institute of Justice found that processing a scene for DNA evidence, following up on leads and eventually identifying a suspect adds about $4,502 to the cost of a property crimes investigation.
That expense has paid off in Denver, where the average sentence in property crime cases using DNA evidence jumped to 14 years, compared with 11/2 years for those without DNA. Part of the reason: Suspects identified in the DNA database are habitual offenders and can be linked to more than one crime. Morrissey estimated that Denver saved more than $500,000 in stolen property and police time between November 2005 and July 2007 by removing repeat offenders from the streets.
Property crimes such as burglary, theft and auto theft cost Americans an estimated $17.6 billion in 2007, according to the FBI.