Briana Carter, 21, was last seen at Midtown Billiards. She spoke with a police officer before leaving, according to an ABC report.

LITTLE ROCK, Ark. — Briana Carter, the 21-year-old woman killed in a head-on collision with an ambulance in January tested positive for alcohol, according to a post-mortem toxicology report.

Carter was found to have a vitreous ethanol content of 0.164 percent. There is a standard deviation of 0.008 percent associated with the results.

An Alcoholic Beverage Control investigation showed Midtown Billiards was not at fault for the accident.

Carter arrived at the bar at 1:18 a.m. on Jan. 9 and left at 4:50 a.m. She had three to four beers and a shot of whiskey.

As she left, she swayed walking to the front door but recovered well enough to leave alone, the report said. Carter stood at the front door talking to the front door worker and a Little Rock police officer before she left alone and drove away.

A source that was with Carter said she may have smoked marijuana before arriving at Midtown Billiards. There was no mention of THC in the toxicology report. The lab was unable to perform a full screening because the sample was insufficient for normal testing.

The ABC report said that it is unknown what may have happened after Carter left the bar that may have contributed to the fatal crash just after 5 a.m. on Jan. 9 on I-40.