Garrett Hedlund is still being haunted by his 2020 DUI bust ... because now he's facing a lawsuit from a family that claims he crashed into their car before being arrested.
According to a lawsuit, obtained by TMZ, the family members -- a mother and her 3 children -- claim they were riding in a Nissan Sentra when Garrett passed out drunk behind the wheel of his Jeep, ran a red light and slammed into them.
In the docs, the family claims the "Troy" actor was driving at a high rate of speed and was over twice the legal limit for alcohol at the time of the crash. They also claim he tried to flee the scene after the accident and didn't call an ambulance for them.
The mom says she and her 3 children were eventually transported to different hospitals after sustaining injuries in the Jan. 24, 2020 crash.
Garrett was arrested for DUI that same night and court records show he pled no contest to a DUI charge in Feb. 2020, and was sentenced to 3 years probation.
The family is suing Garrett for damages.
We reached out to Garrett's camp ... so far, no word back.