West Midlands PC Zaid Malik was off duty when he got into an argument with another driver in Birmingham.
He convinced friend Roger Baker, 50, to provide a false alibi. Both denied a charge of conspiracy to pervert the course of justice.
Malik, 51, of Sparkhill and Baker, 50, of Acocks Green, were jailed for 21 months and 12 months respectively.
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West Midlands Police said the incident took place in Stechford on 26 February 2015.
The force said witnesses accused the former Coventry-based PC of being the aggressor, but police decided not to press charges when a seemingly independent account from Baker backed Malik's claim he was the innocent party.
Police said investigators became suspicious after revealing inconsistencies in the men's statements. They discovered the two were friends and Baker, of Westfield Road, had not been at the scene of the dispute.
Both men were found guilty following a trial and sentenced on Tuesday at Birmingham Crown Court.
Malik, of Durham Road, continued to work for West Midlands Police in a role outside the evidential chain up to his court appearance.
The force said a special case hearing would be held with Chief Constable Dave Thompson to determine his future.
Ch Insp Brian Carmichael, from the Professional Standards Department, said: "We demand the highest standards from all our officers. The public should expect to be treated fairly and respectfully."
A police officer has been jailed for lying about his part in a road rage row.