(NewsNation) — Tom Mauser, the father of Columbine victim Daniel Mauser, says he was “pleased” to learn about Jennifer Crumbley’s “long-overdue” guilty verdict.

Jennifer was found guilty Tuesday on four counts of involuntary manslaughter for her role in the Michigan school shooting committed by her son Ethan Crumbley.

Mauser told NewsNation’s Ashleigh Banfield he believes Jennifer’s husband, 47-year-old James Crumbley, who is also facing four counts of involuntary manslaughter, should face the same verdict. His trial is set to begin in March.

“When I heard her (Jennifer) comment that she had wished that the school had shown they were concerned about her son. I thought it was so ironic,” Mauser said during an exclusive appearance on “Banfield.” “Why didn’t she and her husband show the same concern about their son? … It’s the responsibility of both parents to secure a gun. You don’t provide a gun to a 15-year-old kid who was troubled.”

The jury reached its verdict four days after the prosecution and defense gave closing arguments on Friday.

Ethan pleaded guilty to the school shooting that killed four teens at Oxford High School in 2021. But in a first-of-its-kind move, prosecutors charged both his parents for their role in the shooting, saying their negligence led to the shooting.

Prosecutors say Ethan’s parents were grossly negligent when she failed to tell Oxford High School officials that the family had guns, including a 9mm handgun that was used by their son at a shooting range just a few days earlier.

Besides knowledge of the gun, the Crumbleys are accused of ignoring their son’s mental health needs. In a journal found by police in his backpack, the son wrote his parents wouldn’t listen to his pleas for help.

NewsNation’s Urja Sinha contributed to this report.