The defense for a 22-year-old local man on trial in Guam for the deaths of three Japanese tourists and the wounding of 11 people in February of last year rested its case Wednesday by asserting that he is insane, using testimony by psychiatric experts.

Martin Blinder, a California-based psychiatrist with 40 years of experience, took the stand as the last defense witness on Wednesday, stating that the defendant, Chad Ryan De Soto, "suffered one of the most severe depressions that I have experienced in my long professional life."

De Soto stands accused of multiple aggravated murder and multiple attempted aggravated murder. Multiple aggravated murder carries a maximum penalty of life imprisonment without parole.

Prosecutors allege that on Feb. 12, 2013, De Soto deliberately drove his car into a group of Japanese tourists in Guam's main tourist district of Tumon before crashing into a convenience store, getting out of the vehicle and stabbing people at random.

The defense has pleaded not guilty, citing mental illness.

On Tuesday, Karen Fukutaki, another psychiatric expert tapped by the defense to examine De Soto, testified that she found the defendant to have met two of the three criteria of Guam's insanity statute.

The first psychiatrist to examine De Soto, Michael Kim of the U.S. Navy Hospital in Guam, testified Monday that while the defendant showed symptoms of depression, he did not find his competence was an issue.

The defense and the prosecution are expected to deliver their closing statements next week.