Actor allegedly did several shots of vodka before driving

While the investigation into Lane Garrison's car accident that killed a 17-year-old boy is still underway, witnesses who attended a party with the actor that night say they saw him drinking heavily.

According to TMZ.com, five eyewitnesses say that the "Prison Break" actor drank "several shots" of Grey Goose vodka before climbing behind the wheel of his Land Rover, which ultimately ended up hitting a tree on Saturday, Dec. 2. The fatal crash killed one passenger, Beverly Hills high school student Vahagn Setian, and injured two 15-year-old girls.

The witnesses say that Garrison arrived at the party with the aforementioned kids in tow. He reportedly brought his own bottle of Grey Goose vodka, did numerous shots and offered shots to others at the party. Photos of Garrison drinking were allegedly taken. When the alcohol ran low at the party, Garrison and the three students drove off to buy more. After four hours, some partygoers became worried, and when they couldn't find them, they went to Cedars-Sinai Medical Center where they learned that Setian had died.

Garrison's attorney Harland Braun claims that his client probably wasn't intoxicated at the time of the accident and only had one margarita at a restaurant earlier in the night and one drink at the party. A blood sample was taken at the hospital, but lab results to determine Garrison's blood-alcohol level could take as long as two weeks.

"Who knows if someone put something in his drink at the party," says Braun, who also added that lately, Garrison's SUV has been having problems with its alignment and brakes. "Nobody knows what happened, it's a mystery."

According to Braun, Garrison met the three teenagers for the first time Saturday at a gas station or supermarket, depending on the account. The actor was rendered unconscious in the accident, and when he awoke in the emergency room at the hospital, he had a taxi coupon in his lap and had to be told what had transpired earlier. When he learned of Setian's death, Braun says his client was "totally despondent."

Garrison, 26, is best known as the petty thief David "Tweener" Apolskis, who successfully escaped from jail on "Prison Break," but was later shot and killed.