Steven Barnes sat down to Thanksgiving dinner with his family for the first time in 20 years. The 42-year-old man walked out of state prison Tuesday after spending nearly half his life behind bars for a crime he did not commit.

An Oneida County Court judge set Mr. Barnes free after DNA testing exonerated him of the murder and rape of a 16-year-old girl.

At the time of Mr. Barnes's conviction on murder and related counts in 1989, DNA testing was still in its early development and could not provide conclusive evidence.

The family did not give up on their belief in Mr. Barnes's innocence and persuaded the Innocence Project to take up their cause in 1996. The organization has helped free more than 200 wrongfully convicted persons, many of them on death row.

A second DNA test also proved inconclusive because genetic material had deteriorated. But as DNA testing became more sophisticated, a third test this year "definitively excluded" Mr. Barnes as a suspect.

The district attorney conceded that Mr. Barnes "would never have been arrested" if today's DNA technology had existed in 1985. The search for the real killer has been renewed.

For the family of the murder victim, it means reopening and reliving the tragedy while knowing that her murderer has been free all these years.

Mr. Barnes will be catching up with a much-changed society as he learns how to use the Internet and a cell phone, a reminder of a justice system that can fail. He was fortunate to have the perseverance of his family and intervention of the Innocence Project to correct this injustice.