After a 15-year-old school shooter pleaded guilty to all charges and was sentenced to life in prison, prosecutors argued he wasn’t the only one to blame. His parents were each convicted of four counts of involuntary manslaughter for failing to secure the gun and for gross negligence in not ensuring their son got the mental health care he needed. They were sentenced to at least 10 years in prison. It is the first time that parents in the U.S. have been held criminally responsible for a mass schoo