A former Colorado cop has been charged with second-degree murder for having fatally shot a 17-year-old boy the night before Thanksgiving after it was determined he was drunk at the time.

The shooting took place in the city of Aurora in the US state of Colorado on the night of 24th November.

Adam Holen, 36, a former police officer in the municipality of Greenwood Village, was found to have been drunk at the time of the shooting, according to the court affidavit.

The victim, Peyton Blitstein, 17, was shot a minimum of four times during a gunfight with the cop outside a home on South Addison Way, and later died of his injuries.

The affidavit says Holen, who had left the Greenwood Village police force weeks before the shooting, was hit in the hip and was discharged from hospital the next morning.

The former cop has been formally charged by the 18th Judicial District Attorney’s Office for second-degree murder, prohibited use of a weapon while drunk, felony menacing, and two violent crime sentence enhancers.

During questioning, Holer said he had been visiting his mother when a red Toyota Scion “nearly crashed” into his car and cut him off at speed.

The Toyota pulled up outside a home on South Addison Way, where Holer lived, and the former cop shouted at the teenagers in the car to stop speeding.

The affidavit says that the teens denied driving aggressively or speeding, adding that Holer was probably the primary aggressor as he made first contact and chose to stay at the scene and argue rather than return home.

The ex-cop and the teens then became embroiled in a heated row, leading to them both brandishing firearms.

According to prosecutors, Blitstein, armed with a ‘ghost gun’, made from different parts and not traceable to a seller, shot first at Holer who immediately returned fire.

The affidavit says that Holen was advancing on the teen with a gun in his hand when he opened fire.

The investigation continues.