MILWAUKEE (AP) -- A Milwaukee man who served 23 years in prison for murder is free today. But that leaves the crime unsolved and people wondering whether the real murderer has been on the loose all those years.

Forty-four-year-old Robert Lee Stinson had his conviction overturned after the Wisconsin Innocence Project used DNA evidence and bite-mark technology to discredit the evidence that sent him to prison.

Stinson hugged his sister after being released in New Lisbon yesterday. He expressed his gratitude for the Innocence Project and headed home to Milwaukee, where prosecutors have six months to decide whether to retry him for the murder of a 63-year-old neighbor.

She was found beaten to death and nearly nude in an alley near her home one morning in 1984. A friend told police she dropped the woman off after midnight, after they had gone on a bus trip to Indiana to play bingo.

The victim had extensive injuries and bite marks.