The Fresno Bee reported ( http://bit.ly/1k6aWVh) that a jury on Friday also convicted Dustin Gran of lying in wait, conspiracy to commit murder, theft and burglary.
He faces life in prison for the slaying of 18-year-old Krista Pike.
Prosecutors say Gran planned the murder with 22-year-old Brittany Navarra, who is also awaiting trial for Pike's murder.
Authorities say Navarra goaded Gran into killing Pike by sending him inflammatory text messages. Detectives say Gran also photographed Pike's dead body with a cellphone camera.
The jury will return Wednesday to determine whether Gran was legally insane when the crimes occurred.
Information from: The Fresno Bee, http://www.fresnobee.com