Brian Hall didn't plan to kill Rosella Atkinson 20 years ago, a Common Pleas jury decided yesterday.
The jury, responsible for determining Hall's degree of guilt after he stood before them and admitted to the deed, found him guilty of third-degree murder.
Prosecutor MK Feeney was seeking a first-degree conviction for the long-unsolved case.
Defense attorneys Helen Levin and Steve Gross argued that Hall did not have the intent to kill when he strangled the 18-year-old mother to death in a field next to Central High School's football field in 1987.
When Hall - moved by his nagging conscience - finally confessed to the crime in 2005, he said he "put my hands around her neck" because he believed Atkinson had stolen money from him after they went to the Olney field to have sex.