A process that could match a genetic DNA blueprint to relatives of a suspected criminal is currently only used in California, Colorado and Virginia.
A man who has been convicted three times with the rape and stabbing death of an 11-year-old girl nearly 20 years ago was back in court this week fighting for another appeal.
At the same time, a team of lawyers representing the man, Juan Rivera, are pushing for a change to Illinois law that would allow the use of a process called "familial DNA testing" that they say would exonerate him.
When investigators have a DNA profile they can't identify, the special testing allows them to use a genetic blueprint to search the existing database for relatives of that profile. Many times that partial match can steer the investigation and help authorities track down a suspect.
To confirm the man killed in Pakistan was Osama bin Laden, American investigators last month used DNA from bin Laden's sister. In California, police used DNA from a man to track down his father, who is suspected of being the "Grim Sleeper."
"The technique is only used when other investigative techniques have been exhausted," said Judy Royal, an attorney with Northwestern Law School's Center on Wrongful Convictions and a member of Rivera's legal team.
Rivera in 1992 was convicted in the death of Holly Staker of Waukegan and since then has been serving a life sentence at Stateville Prison in Joliet. His conviction has been appealed three times, and each time a jury has found him guilty.
But during his last trial, in 2009, advancements in technology allowed investigators to test DNA recovered from Staker's body. The genetic profile recovered from the fingerprints, hair and other evidence collected at the scene of the crime could not be traced back to Rivera, nor was it a complete match of any other profile already in the national database.
"I'm not the person who committed this murder," Rivera insisted during an interview with NBC Chicago, his first from prison. "I refuse to plead guilty to something I didn't commit. I'd rather die in prison as an innocent man."
The majority of the case prosecutors built against Rivera revolved around a confession he signed. Though he admits to initially lying to investigators about where he was the night of the crime, Rivera argues the confession he signed after a four-day police interrogation was coerced.
"I lost consciousness. I blacked out. I don't remember anything that occurred," he said.
Rivera's attorneys believe familial DNA testing on the evidence recovered from Staker's body could create a new lead and are pushing to get Illinois leaders to allow the technology.
"We have a very clear profile," said Royal. "We just don't have the name of the individual whose DNA that is."
California, Colorado and Virginia are currently the only states that regularly implement familial DNA testing.
Despite its promises, familial DNA testing does come with controversy.
The American Civil Liberties Union contends the testing method is an invasion of privacy that could lead to racial profiling.
"African-Americans and Hispanic-Americans are far more likely than white Americans to be subjected to criminal investigations as a result of familial DNA testing. This is due to differences in birth rates and incarceration rates," said Adam Schwartz, a senior lawyer with the ACLU of Illinois.
Still, Royal is convinced the familial DNA testing is worth the risk.
"The privacy concerns are outweighed by the importance of catching a criminal of a violent crime," she said.
Illinois has no firm plans for familial DNA testing yet, though implementing it in the Land of Lincoln could happen a number of ways, including a vote by state legislators or an executive order from the governor's office.
Illinois Attorney General Lisa Madigan supports the procedure. Her office, in a statement, said it is actively working to bring the technology to the state.
"Familial DNA testing would be an invaluable tool for law enforcement to both identify potential suspects and exonerate those wrongly accused. The debate surrounding the use of familial DNA is occurring across the nation, and we are leading those talks here in Illinois. We intend to proceed cautiously, however, to ensure that privacy and civil rights are taken into account and protected as we look to develop a process for utilizing this technology to bring about justice."
Attempts to reach Holly Staker's family for comment were unsuccessful.