A High School Fight Ended With 1 Boy Stabbed to Death and the Other Charged With Murder. That Trial is Now Underway

The murder trial of a high school student who admitted to stabbing his classmate to death kicked off in Texas this week.

Caysen Allison, now 21, confessed to killing Jose Luis Ramirez Jr., 18, during a fight in the boy’s bathroom at Belton High School back on May 3, 2022, according to an arrest affidavit obtained by PEOPLE.

Allison’s lawyer, Zachary Boyd, said in his opening statement that the then-18-year-old acted in self defense after finding himself forced to fight Ramirez and a group of his friends.

Allison, who has been on house arrest ever since posting $175,000 bail back in July 2022, is facing anywhere between 5 and 99 years in prison if convicted.

The murder trial began with opening statements on Monday, and on Tuesday jurors were shown video of the stabbing that one of Ramirez’s friends recorded inside the bathroom.

That video allegedly shows Ramirez throwing a punch at Allison and Allison responding by swinging at Ramirez with a knife in his hand, according to court documents. It then allegedly ends with Ramirez cornered before the teenagers all run out of the bathroom.

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The arrest affidavit details the aftermath of the fight.

Ramirez manages to leave the bathroom but is seen on school surveillance video collapsing in the hallways a short time later while blood pours out of his body, according to the affidavit.

The school nurse then started to perform life-saving measures on Ramirez, who was then transported to a local hospital where he was later pronounced dead. The affidavit notes that Ramirez had been stabbed in the chest, back, legs and arm.

Allison left school and returned home after the fight and was arrested a short time later, according to the affidavit.

A knife covered in blood was allegedly found at Allison’s house, per the affidavit.

Court records show that an additional charge was filed against Allison a few days later on May 9 after he allegedly assaulted a family member.

Allison has entered a plea of not guilty and the trial is expected to last through next week.