Chicago police disciplinary officials have ruled that an officer was unjustified in the fatal 2015 shooting of a baseball-bat clutching 19-year-old and an innocent bystander.

The Civilian Office of Police Accountability determined that Officer Robert Rialmo unjustifiably shot Quintonio LeGrier and 55-year-old Bettie Jones while responding to a domestic disturbance on the West Side on the day after Christmas two years ago, according to documents obtained by the Tribune through an open records request.

After LeGrier approached officers with an aluminum baseball bat, Rialmo shot the teen and accidentally hit Jones, a neighbor standing nearby.

The ruling, dated Dec. 22, turns in part on investigators’ determination that the evidence indicated that LeGrier did not swing the bat at Rialmo, as the officer has said. Investigators also found that the evidence — including shell casings, witness statements and forensic analysis — also suggested Rialmo was farther away from LeGrier when he fired than the officer has said. LeGrier fell in the vestibule of an apartment building, and Rialmo said he opened fire from the building’s front porch, but investigators determined it was more likely the officer was between the bottom of the porch and the sidewalk out front.

The agency concluded that a “reasonable officer” would not have believed he was in danger of death or serious injury.