Two men allegedly got into an altercation in a suspected road rage incident in Conder, police say.
The driver of a silver Hyundai Getz allegedly rear-ended a white Ford ute about 4.30pm on May 16.
Police say the men got out of their cars and were involved in an altercation on the corner of Chartsville Avenue and Box Hill Avenue, Conder.
A woman driving a blue Mazda 3 was also in the street when police arrived.
All three drivers were breath tested, and the driver of the Getz returned a blood alcohol content of 0.186, more than three and a half times the legal limit.
The drivers of the Getz and Ford ute also allegedly had interactions travelling southbound on the Monaro Highway from Fyshwick to Gilmore in the lead-up to the collision.
Police say further charges are expected to be laid.
Anyone who saw these interactions, or who may have dash-cam footage of the vehicles travelling on the Monaro Highway, is urged to contact Crime Stoppers on 1800 333 000, or via the Crime Stoppers ACT website. Please quote reference 7750439. Information can be provided anonymously.