Under current Pennsylvania law, DNA samples may only be taken from suspected or convicted offenders under two narrow circumstances. A sample may be taken from a suspect charged with a crime only if police have obtained a search warrant, or a sample may be taken from an offender who has actually been convicted of a crime.

Recently, Pennsylvania lawmakers have proposed legislation which would significantly expand DNA sampling, requiring suspects who are charged with any felonies and with certain misdemeanors to give DNA samples. Police would then have the power to compare that sample to those taken from crime scenes across the state and in the FBI's DNA registry, potentially adding to the charges against the suspect.

The American Civil Liberties Union of Pennsylvania has voiced its objections to the bill, arguing that it will allow suspects' DNA to be used in criminal investigations with no probable cause to believe that the suspect is involved in the crime being investigated. In addition, opponents have raised the common occurrence of a suspect being charged with one crime and being convicted of a different, lesser crime that would not require a DNA swab. The bill does not address what will happen to the DNA sample in that situation.

Sgt. Joe Gannon of the Pittsburgh Police Department's sexual assault squad says that the bill will also help suspects instead of merely adding to the potential of harm. "I think it's a good thing both ways," he said. "It can work to help prove a case and it can help to exonerate a person."

The bill was most recently heard in the Senate Judiciary Committee, and its next step is unknown.

Source: Pittsburgh Tribune-Review, "Pennsylvania measure would expand DNA sample collection", Brad Bumsted and Margaret Harding, 21 March 2011