Brent is charged in connection with a Dec. 8 crash that killed his friend and Cowboys practice squad member Jerry Brown. Brent is out of jail on $100,000 bond.
Dallas County District Attorney's Office spokeswoman Debbie Denmon says the indictment was returned Wednesday.
Police in the Dallas suburb of Irving say Brent was speeding when his vehicle struck a curb and flipped. Brown was pronounced dead at an area hospital.
Intoxication manslaughter carries a maximum sentence of 20 years in prison. Brent could be eligible for probation.
Denmon says no court dates have been scheduled.