The Boulder County District Attorney’s Office has found a Louisville police officer justified in firing at a suspect driving a truck investigators said rammed into a patrol car.The suspect, identified as 25-year-old Nicholas Moses, was shot in the upper arm. His father, 57-year-old John Moses, was in the passenger seat of the vehicle but not injured, according to the district attorney’s decision letter.The suspect’s pitbull was killed in the June 7 incident, which was the first officer-involved shooting in the history of the Louisville Police Department.Police first responded to the location of the shooting the 500 block of East South Boulder Road after receiving a report of potential drug activity in the area. Nicholas Moses told police that he had shot up heroin earlier in the day, and later admitted that he was behind a bar to try and get more, according to the decision letter.Investigators later found multiple used syringes, heroin and fentanyl in the back of his truck, the letter said.When officers first confronted Nicholas Moses and his father, they were in a pickup truck with a pitbull in the back. The letter said Nicholas Moses initially complied with commands from police, but later got back into the truck and rammed into officers.Efforts to use a stun gun on him were not successful, according to the letter, and the officers involved in the incident were justified in firing their weapons.Both John and Nicholas Moses are being held on separate warrants.