Santa Clara County District Attorney Jeff Rosen, announcing that the 1978 murder of teacher Diane Peterson had been solved by the DA’s cold case unit.
The suspect, Harry “Nicky” Nickerson, a 16-year-old at the time, was the person who stabbed Peterson in her classroom. Nickerson, who had been an early suspect in this case, died by suicide in 1993.
In 2023 and 2024 extensive DNA testing was done in the case, but authorities were unable to identify any forensic evidence to connect the murderer to the crime. Death was caused by a single stab wound, committed in a public place and there was no sexual assault.
Deputy DA Rob Baker explained: “Once we determined there wasn’t any physical evidence that was going to help us corroborate these claims or identify the killer in this case, the detectives just decided, you know what, we’re just going to reach out to the people who were closest to Mr. Nickerson and see if he made any statements to them. See if they have any information to close the loop on this case to try to give answers and closure to the family.”
San Jose Police Chief Paul Joseph reminded the community: “Let this serve as a solemn reminder: no matter how much time passes, we will continue to seek the truth – because every victim matters, and every life deserves justice.”