Nicholas James Yarris, 42, of Philadelphia has been on death row since for 21 years....half of his life. Today at a press conference, his lawyers, Peter Goldberger and Christina Swarns, announced that DNA testing has cleared him.

Recent tests show that Yarris' DNA did not match physical evidence left on the victim's clothing and under her fingernails, said Swarns, of the Federal Defender Association of Philadelphia. The association said that Yarris is the first person on death row in Pennsylvania to be cleared by DNA testing.

In the late 1980s, Yarris -- who has maintained his innocence -- was one of the first prisoners in Pennsylvania to demand DNA testing. Test results done in at a state police lab in 1992 were inconclusive. After Yarris exhausted his state court appeals, federal defenders took over the case and in 1997 demanded new tests, which were completed last week by a private lab in Richmond, Calif., Swarns said.

Each piece of evidence kept by the Delaware County District Attorneys Office-- gloves left in the victim's car, the victim's underwear and skin samples from under her fingernails -- was retested and each piece excluded Yarris, Swarns said.

The prosecutor has said he will evaluate the new evidence. So does this mean the system works? No.

"The fact that after 21 years Yarris was lucky enough to have this evidence discovered is by no means proof of the system working," said Jeff Garis of Pennsylvania Abolitionists United Against the Death Penalty.

"The true killer has escaped justice, a young man's life was destroyed and the limitations of our justice system have been exposed."

Since DNA evidence is available in only a small number of homicide cases - approximately 15% -- this exoneration should cause us to consider the fact that 85% of death penalty cases can never be 'scientifically verified.' An erroneous conviction of this magnitude is ample evidence of a problem. The vast majority of reasonable people - both for and against the death penalty - can agree that no executions should take place until we can be certain that there aren't other innocent people on death row."

This case is another glaring example of why a moratorium on the death penalty is needed.

Update: Here's some more news on the case.