A policeman rammed a patrol car into a man's car before he and a colleague lodged a report claiming the other driver deliberately reversed at them, a court has heard.

One of the officers, Brennan Roberts, 26, on Monday pleaded guilty to making a false report on the night of August 22 last year, following a collision between the man's car and the police vehicle in Hillside, in Melbourne's north-western suburbs.

Roberts must now wait until October 16 to learn if he has an outside chance of retaining his job, depending on whether magistrate Charlie Rozencwajg imposes a conviction in sentencing.

Melbourne Magistrates Court heard Roberts and the other officer said in their reports the other driver, Anthony Vittori, had reversed his Honda into the police vehicle, when it was the other officer who had rammed the patrol car into the rear of Mr Vittori's car.