A Georgia judge sentenced Colin Gray to 15 years in prison after he was convicted in connection with the 2024 Apalachee High School shooting carried out by his son, Colt Gray.
The case marks one of a growing number of prosecutions in which a parent has been held criminally responsible for a school shooting committed by their child.
Colin Gray, 55, was convicted of second-degree murder in the deaths of students Mason Schermerhorn and Christian Angulo, and involuntary manslaughter in the killings of teachers Richard Aspinwall and Cristina Irimie.
The sentencing came days after Colt Gray, now 16, received a life sentence without the possibility of parole for the September 4, 2024, attack.
Judge Nicholas Primm, who presided over both cases, said Colin Gray had "failed as a parent" while emphasizing the need to distinguish the father's conduct from that of his son.
The judge rejected requests from prosecutors for an 80-year sentence and from the defense for 10 years in prison followed by probation, ultimately imposing a 15-year prison term.
Primm said the legal process required him to set aside emotion despite the impact of the shooting on victims and their families.
He also stated that Colin Gray could have prevented the attack by securing firearms, restricting ammunition access, or obtaining mental health treatment for his son.
Prosecutors argued that Colin Gray ignored multiple warning signs about Colt Gray's deteriorating mental state before giving him a SIG Sauer SIGM400 rifle as a Christmas gift.
Evidence presented during the trial showed that family members, including Colt's mother, Marcee Gray, had urged Colin Gray to lock up the family's firearms and limit the teenager's access to them.
The shooting left four people dead and injured another teacher along with eight students.
Victims' relatives told the court the tragedy was preventable and urged the judge to impose the maximum sentence.
The case follows similar prosecutions in the United States, including the convictions of Jennifer and James Crumbley in Michigan, reflecting increasing efforts by prosecutors to hold parents accountable when their actions are found to have contributed to school shootings.
Judge Primm said the sentencing closed only the legal chapter of the case, while acknowledging that the pain experienced by victims and their families would continue.