A Michigan judge is poised to decide Friday if the teenaged gunman who killed four students at his high school can be sentenced to life in prison without parole.

Ethan Crumbley, now 17, also injured seven other people when he opened fire at Oxford High School in November 2021.

He pleaded guilty last October to one count of terrorism causing death, four counts of first-degree murder and 19 other charges in connection to the rampage.

Oakland County Circuit Court Judge Kwamé Rowe is expected to issue a ruling during a remote hearing early Friday that will decide if prosecutors met their burden to prove a life term without parole is a proportionate sentence for Crumbley, who was 15 at the time of the mass shooting.

A life sentence without parole is the harshest punishment available in Michigan.

Over four days in July and August, Oakland County prosecutors and Crumbley's defense team presented witness testimony and evidence at a so-called Miller hearing -- a hearing required by law when prosecutors seek a life sentence without the possibility of parole for a minor defendant.

Prosecutors argued the premeditation of Crumbley's attack was justification for a finite life sentence. They played audio messages in court in which the teen said, "I am going to be the next school shooter," and that he would "have so much fun."

The shooter can alternatively be sentenced to life in prison but could be eligible to appear before a parole board at some point.

In seeking a prison sentence with parole eligibility, defense attorney Paulette Loftin asked the judge to consider mitigating factors like Crumbley's difficult home life and ignored pleas to his parents for mental health treatment.

Loftin also asked the court to give Crumbley a chance at rehabilitation and to allow a parole board to determine his progress years from now.

Oakland County prosecutor Karen McDonald conceded Crumbley's parents were negligent during her closing argument at the hearing, but said that doesn't outweigh the act and other factors.

"We have to deal with the darkness and the violence, and we have to accept that it happened. And we can also say we wish he had a better upbringing. But we're not going to ignore facts -- and the facts are that he had a choice," the prosecutor said.

"He had many opportunities. He plotted, he planned, he showed none of the mitigating factors and evidence that you see in hundreds of other juvenile life without parole cases," McDonald added.

Students and faculty who survived the shooting testified about their experience coming face to face with the shooter at the hearing. Expert witnesses from both sides gave dueling testimony about the effects of the shooter's difficult home life, his mental health and how likely it is that he can be rehabilitated in prison.

The shooter's parents, who were arrested days after the shooting and charged with four counts of involuntary manslaughter, remain in jail pending that case, in which Oakland County prosecutors say Jennifer and James Crumbley gave their son easy access to a firearm and disregarded signs he was a threat.

The teenager, who has been detained at the county jail since his arrest at the school the day of the shooting, is scheduled to be sentenced December 8.

Surviving shooting victims and family members of the victims are expected to give victim impact statements at the sentencing hearing in Pontiac, Michigan, before Rowe hands down Crumbley's sentence.