A New Hampshire town and two police officers involved in the fatal shooting of a man who lunged at them with a knife in 2015 say they are protected from liability in a lawsuit filed against them by the man’s mother.

The mother of Hagen Esty-Lennon, of Canterbury, sued in February, alleging officers violated her son’s constitutional rights.

The New Hampshire Attorney General’s office ruled the Bath, New Hampshire, shooting, which was captured on police videos, was “legally justified.”

The town, Officer Ryan Jarvis, and former Officer Gregory Collins, filed a motion Friday saying they are protected from liability for wrongful death under several state laws on civil immunity, physical force in law enforcements, and bodily injury actions against government agencies.

The Caledonian Record reports a lawyer for the town and Jarvis said neither officer used deadly force until Esty-Lennon was less than 15 feet away.