PORTLAND — A Portland man serving 60 years in prison for strangling his girlfriend and cutting off her head was not insane at the time of the killing and is criminally responsible for his conduct, Maine’s highest court ruled today.

In a unanimous decision, the Maine Supreme Judicial Court rejected Chad Gurney’s appeal of his murder and arson convictions for killing 18-year-old Zoe Sarnacki on May 25, 2009, in his apartment and setting fire to her body to cover up the crime.

A superior court judge last year rejected Gurney’s insanity defense. On appeal, Gurney’s attorney told justices that Gurney, 30, wasn’t criminally responsible because he was suffering mental problems and having a psychotic episode that made him delusional.

During the trial, the defense contended that Gurney’s mental health problems started at Liberty University in Virginia when his lacrosse team’s 15-passenger van crashed in 2005. He suffered a severe head injury and other injuries that led to 20 surgeries. He later returned to Maine and lived off a multimillion-dollar insurance settlement.

Gurney’s attorney said Gurney’s psychotic break stemmed from a combination of his head injury and withdrawal from medications.

But prosecutors maintained that Gurney was simply angry because Sarnacki had slept with someone else while he was out of town, and later refused his request to quit her job at a bagel shop and join him on a trip to Thailand, where he hoped to further his interest in Eastern religion.

Only subscribers are eligible to post comments. Please subscribe or to participate in the conversation. Here’s why.

Use the form below to reset your password. When you've submitted your account email, we will send an email with a reset code.