A jury on Friday found Richard Tuite not guilty of voluntary manslaughter. His 2004 conviction had been overturned but he's already served most of the original 17-year sentence.
Prosecutors said Tuite sneaked into an Escondido bedroom in 1998 and repeatedly stabbed Stephanie Crowe.
Authorities charged the girl's teenage brother and two of his friends with the killing but dropped the charges after drops of her blood were found on Tuite's clothing. The boys' families later settled a false arrest lawsuit for $7 million.
Tuite's attorney, Brad Patton, argued the blood on the clothing was due to crime scene analysis contamination and he was never in the house.