They don't have his name or address, but prosecutors say they've got what they need to charge John Doe with burglary: his DNA.
The unnamed suspect -- identified in court records by only his genetic profile -- was indicted this week as DuPage County prosecutors sought to get his case on the books well before the statute of limitations expires.
The practice is increasingly common, said State's Attorney Bob Berlin, whose office has filed more than 40 cases naming DNA profiles since 2004.
"Anyone can change their name and anyone can change their appearance. But your DNA profile never changes," Berlin said. "There's probably no better way of identifying somebody. In essence, that profile is the defendant."
The suspect is accused of burglarizing a house on the 400 block of West Terrace Avenue in Villa Park on March 3, 2011. Roughly $150 in household items and jewelry was taken, Villa Park Detective Sgt. Dan McCann said Friday.
Neither McCann nor Berlin would elaborate on how the DNA evidence was acquired because the suspect has not been located. But Berlin said a forensic examination showed it came from a man.
Investigators compared the profile with those in a nationwide database of felony offenders for about a year without finding a match before recently taking the case to the grand jury. Berlin said the statute of limitations on the case would have expired in 2014 if no charges were filed. It will now remain open.
"When we get word that there's a match, we go back to the grand jury and get testimony that the profile does match," he said. "Then we amend the indictment to identify the offender and get a warrant."
Some similar attempts in the past proved successful, with offenders eventually being located, Berlin said. He said other states are taking a similar approach.
"The science of DNA has really changed the entire criminal justice system," he said. "In this sense, it's a tremendous tool for law enforcement because it takes years sometimes before you can identify somebody."
But legal experts say it doesn't guarantee the prosecution will get a conviction, depending on the quality of the DNA and how it fits with other evidence.
"If you're charged with a crime where they have other evidence that links you to the scene, and then they come in and say your DNA is a match, that's really different from if they just drag you in out of the blue," said David Taylor, a law professor at Northern Illinois University in Dekalb.
Marc Falkoff, another NIU law professor, said there are several states where the procedure of charging by DNA has been challenged unsuccessfully. Much of the debate centers on whether defendants' due process rights are being upheld, and whether prosecutors are circumventing statutes of limitations.
"You have to assume the general assembly passed the statute of limitations on sex crimes because it didn't want somebody being charged with a sex crime six years after it happened," Falkoff said. "If there's a problem with the statute of limitations, then get rid of it."