FORT LAUDERDALE, Fla. — A former college student who randomly killed a Florida couple in his garage six years ago and then bit into the face of a victim will finally go to trial Monday, with a judge to decide whether he will go to prison for life. or to a psychiatric hospital.

Austin Harrouff, 25, has pleaded not guilty by reason of insanity to two counts of first-degree murder and other charges in the August 2016 murders of John Stevens, a 59-year-old landscaper, and his wife of 53 years. Michelle Mishcon Stevens, who retired after working in finance.

The former Florida State University student has waived a jury trial, which means Circuit Judge Sherwood Bauer will decide whether Harrouff was insane when he killed the couple and seriously injured the neighbor who came to his aid.

The trial has been delayed by the pandemic, legal disputes and Harrouff’s recovery from serious injuries sustained while drinking a chemical during the attack. It will be in Stuart, an hour’s drive north of West Palm Beach, and will run for about three weeks.

Prosecutor Brandon White did not respond to a call and an email seeking comment. Harrouff’s lead attorney, Robert Watson, declined to comment.

Under Florida law, defendants are presumed to be sane. For Harrouff’s defense to succeed, Watson must prove that he had a serious mental breakdown that prevented her from understanding his actions or that they were wrong through «clear and convincing evidence.» Harrouff has said that he was running from a demon when he attacked the couple.

If convicted, Harrouff will be sentenced to life in prison without the possibility of parole; prosecutors waived the death penalty.

If Harrouff is found to be insane, Bauer will commit him to a secure psychiatric hospital until doctors and a judge agree he is no longer dangerous. That would also be effectively a life sentence, said Craig Trocino, a University of Miami law professor, because «it is highly unlikely» that doctors and a judge would risk releasing a killer as notorious as Harrouff.

Two mental health experts, one hired by prosecutors and one by the defense, examined Harrouff and found that he suffered an acute psychotic episode during the attack. They also found that she could not distinguish between good and evil.

Prosecutors then hired a second expert who said Harrouff was sane, but recently withdrew him saying he has serious health problems. They now have a third expert who believes Harrouff was taking a drug that did not show up in post-arrest tests, but has not tested him.

Lea Johnston, a University of Florida law professor, said only about 1% of felony defendants attempt an insanity defense because the bar for success is so high. About a quarter of them are successful, usually in a pretrial agreement in which prosecutors agree that the defendant’s mental illness meets the standard.

He said that for insanity defenses that do make it to trial, defendants who forgo a jury have more success. Judges understand the system, she said, while jurors often worry that defendants acquitted on the grounds of insanity are released early. They may also question whether treatment in a psychiatric hospital works.

“There are decades of research showing that (the public) is biased against the insanity defense and widely misconstrued,” he said.

Harrouff’s attack made national headlines due to its brutality and randomness; he did not know the victims. He was a 19-year-old with no criminal record, a former football player and high school wrestler who was studying exercise science. He stripped nearly naked and attacked the couple in their open garage with tools he found there. When the police arrived, Harrouff was chewing off pieces of John Stevens’s face.

It took several officers, a taser and a police dog to subdue Harrouff. The officers did not fire at him because they feared hitting Stevens.

Harrouff nearly died from the chemicals he drank in the garage, which burned his digestive system.

Investigators discovered that he bought some hallucinogenic mushrooms a few days before the attack, but his friends said that he destroyed them and no traces were found in his blood. He also did Google searches for «how to tell if you’re going crazy.»

Harrouff’s parents, who are divorced, and others said he had been acting strangely for weeks. Her parents had set an appointment to have him evaluated, but the attack happened first.

His father, Wade Harrouff, told him Television psychologist Phil McGraw that the night of the murders her son left a restaurant where they had been eating without explanation. She walked two miles to her mother’s house and tried to drink cooking oil. Mina Harrouff stopped him, but he poured the oil into a bowl of Parmesan cheese and ate it.

She took him back to the restaurant. wade harrouff, a dentist, told McGraw that he grabbed his son and said, «What’s wrong with you?» He said his son raised a fist, but Wade Harrouff’s girlfriend told him to stop and walked away.

Security video from the restaurant shows Austin Harrouff calmly leaving about 45 minutes before the attack. His mother, before learning of the attack, called 911 and told dispatcher that her son seemed delirious, claiming to have superpowers and that there were demons in her house.

But it was too late: Harrouff walked or ran the four miles to the Stevens’ house.

Austin Harrouff told McGraw that he was running from a demon he named Daniel and has only vague memories of the murders.

He said he met Michelle Stevens in the couple’s garage. She yelled, and «so it’s a blur.»

«I don’t remember what he said, I just remember being yelled at,» Harrouff said. He said he grabbed a machete, but he doesn’t remember why he killed her and her husband.

“It’s like it happened, but I wasn’t aware of it,” Harrouff said.