(Reuters). A Michigan judge heard preliminary evidence Tuesday regarding whether prosecutors have enough evidence to file involuntary menslaughter cases against the parents of a teenager who is accused of shooting four high school students to death.

James Crumbley and Jennifer Crumbley are charged with buying the gun as Christmas presents for their son Ethan (15 years old) and not paying attention to warning signs until the morning of the shooting in Oxford (Michigan). Ethan Crumbley was already charged with the first-degree murder of the victim in the 2021 school massacre that claimed many lives.

They all pleaded not guilty.

The prosecution had called witnesses at the preliminary hearing before Judge Julie Nicholson of Rochester District Court. She will then continue the hearing Feb. 24, and decide if there are sufficient evidence to warrant a trial.

Nicholson said that due to the voluminous nature of the exhibits …., the examination will be continued on February 24, because it is too overwhelming.

As they sat at the defendant’s table in court, the couple were wearing prison clothes. Andrew Smith, Jennifer Crumbley’s supervisor in the real-estate company she worked for, testified. He also described their interactions on the day of shooting.

I need my job. Please don’t judge me for what my son did,” Jennifer wrote in a text to Smith after the shooting that he read on the stand. I was shocked that she worried so much about her job. She seemed more concerned with what was happening than I imagined.

At Oxford High School in North Detroit, forty miles (65km) away from Detroit, six students and one teacher were both killed.

It appears that this is the first instance of parents being charged with involvement in the alleged crimes of their children.

Experts said that although other parents have been accused of killing their children by using unsecured guns in the past, they have not been charged in cases involving younger children.

This was just the latest of a long line of American school shootings that have been deadly over decades.

Ethan was with his father four days prior to the shooting. James Crumbley purchased a 9mm pistol at a gun shop. Prosecutors said that this purchase occurred after Ethan had been there.

His mother wrote the next day that they were “testing out” his Christmas gift at a gun range.

Prosecutors named a few other signs they believe the parents ignored, such as Ethan Crumbley’s search for ammunition using his smartphone.

According to the prosecution, Ethan Crumbley’s drawings depicting a gun, bullet and bleeding body were discovered by a teacher on the morning before the shooting.

After school officials summoned Crumbleys, they arrived at their home. According to McDonald’s, the parents refused the suggestion of sending their son home. They did not check his bag or ask about the gun.