July 7 (UPI) — Maryland officials said Tuesday that they have declined to charge police officers who fatally shot an autistic man who had called them for help.

Police shot Alex LaMorie, 25, early in the morning of March 1 in Columbia, Md., after he called them to report that he was being harassed and blackmailed.

“After completing its investigation and evaluating all the available evidence, the Office of the Attorney General has determined that the subject officers did not commit a crime under Maryland law,” said the announcement by state Attorney General Anthony G. Brown. “Accordingly, the attorney general has declined to prosecute the subject officers in this case.”

The attorney general’s Independent Investigations division, which is in charge of investigating and prosecuting police-involved incidents, issued the finding. Officials said they would be unable to secure a conviction of the officers for use of force or homicide offenses and that they would not be able to disprove self-defense on the officers’ part.

In their report, investigators said LaMorie refused police orders to drop a knife and moved toward them before they shot him. State police collected 12 cartridge casings from the scene, The Washington Post reported.

Police said LaMorie made suicidal statements on the phone before they arrived. Officers’ body-camera footage showed he did not lift the knife in their direction, The Post reported.

Jill Harrington, LaMorie’s mother, said in a statement to the Post that the officers should have been charged with involuntary manslaughter and that they “treated Alex’s life-threatening behavioral-medical crisis like a crime.”

“It represents a step backward, and risks undermining the state’s committed progress toward a more humane and effective crisis response system,” Harrington said.

LaMorie lived at Patuxent Commons, an inclusive housing community for those with and without disabilities. He’d moved there days before the shooting.