A silvery blue BMW was heading along Rue à Don towards Gorey at about 20:50 when it hit the central reservation, left the road, and hit a tree just north of the Gorey Common bus stop.
A 26-year-old man was arrested at the scene on suspicion of dangerous driving and driving while unfit.
He remains in police custody while enquiries continue.
Police would like to speak to anyone who saw the crash or the car being driven beforehand. They are asked to ring 612612, call Crimestoppers anonymously on 0800 555111 or make an anonymous report online.