An Irving, Texas, police report obtained by KXAS-TV, Dallas/Fort Worth, said Brent's blood-alcohol level content was more than twice the legal limit in the Dec. 7 crash, and neither Brent nor Brown was wearing a seat belt at the moment the car struck a curb and overturned.
Investigators concluded Brent's car reached speeds of 134 mph after he and Brown drove away from a Dallas nightclub.
Brent told police the vehicle's steering was a "little shaky" but investigators found nothing wrong with the car, and at least three Dallas Area Rapid Transit surveillance cameras captured images of the car as it sped through Dallas and Irving.
Brent was charged with intoxicated manslaughter in Brown's death. He is free on bond and his attorney said the case could go to trial this summer.
Celebrity Families of 2014 [PHOTOS]