Irving, TX- The trial for former Dallas Cowboys defensive tackle began on Monday with his defense attorney arguing that he wasn’t drunk at the time of the fatal crash.

Brent, 25, is accused of being intoxicated when he caused an accident that took the life of one of his former teammates, Jerry Brown in December of 2012.

In his opening statements, Brent’s attorney, Jerry Milner, said his client was “guilty of being stupid behind the wheel,” but contends he was not drunk when the accident occurred, USA Today reported.

Brent was driving that night in December when he lost control of his Mercedes and hit a curb. The vehicle in which Brent and Brown were occupants flipped over at least once and came to rest on the roof. When police arrived they saw Brent dragging his teammate out of the burning car.

Brown, who was seriously injured, was taken to a local hospital where he was later pronounced dead.

Police suspected Brent was intoxicated and subjected him to a battery of field sobriety tests, which was captured by a Dash cam and was showed in the courtroom Monday.

Brent admitted to officers he had a “reasonable amount” to drink, and a blood test showed his blood alcohol level was more than two times the legal limit– .08 in Texas. But Brent’s attorney argued that a man of Brent’s size—he weighs 320 lbs. — could drink more than the average person and not be intoxicated.

“Josh Brent is as big as a house,” Milner said, according to the USA Today. “He’s got a heart — better yet a mind — of a person much younger than he really is.”

Milner also told the court that no one could perform well on field sobriety tests after being involved in a fiery crash. He said there were a number of reasons why Brent performed poorly on the field sobriety; he had a minor head injury, he was too large to maintain his balance and powder from the airbag made his eyes watery.

But the prosecution argued there was no dispute that Brent was drinking that night and produced receipts from the night club he was at earlier that night which showed he bought three bottles of champagne and several liquor drinks.

If convicted of intoxication manslaughter, Brent could face up to 20 years in jail. His attorney is asking he be placed on probation. According to USA Today Brown’s mother has forgiven Brent who retired from the NFL last year, but the prosecution will fight to secure a tough sentence for Brent.

This is the second high-profile fatal DUI trial for Texas in the past month. The first case involved teenager, Ethan Couch, from neighboring Tarrant County, who avoided jail after killing four people in DUI accident last summer because a psychologist testified that the 16 year old suffered from “affluenza.” A condition caused by his privileged life in which he never learned the consequences of his actions.