San Jose cold case: Family confession solves 1978 fatal teacher stabbing, authorities say A then-16-year-old student, who is now dead, is officially named as the killer of Diane Peterson near her ...

Diane Peterson was found dead on a hallway floor near her classroom at a San Jose high school on June 16, 1978, according to the Santa Clara County District Attorney's Office.

Branham High School teacher Diane Peterson was stabbed to death by a 16-year-old boy, Harry “Nicky” Nickerson, on June 16, 1978, the Santa Clara County District Attorney’s Office said.

A June 1978 sketch of the suspect accused of killing San Jose schoolteacher Diane Peterson, left, compared to then-student Harry Nickerson, now identified as her killer, in an undated photo, right.

Decades after Diane Peterson’s 1978 killing at Branham High in San Jose, the suspect, Harry Nickerson, has been identified, Santa Clara County prosecutors say.

Branham High School teacher Diane Peterson was stabbed to death by a 16-year-old boy, Harry “Nicky” Nickerson, on June 16, 1978, the Santa Clara County District Attorney’s Office said.

Decades after Diane Peterson’s 1978 killing at Branham High in San Jose, the suspect, Harry Nickerson, has been identified, Santa Clara County prosecutors say.

Decades after Diane Peterson’s 1978 killing at Branham High in San Jose, the suspect, Harry Nickerson, has been identified, Santa Clara County prosecutors say.

Decades after Diane Peterson’s 1978 killing at Branham High in San Jose, the suspect, Harry Nickerson, has been identified, Santa Clara County prosecutors say.