ROSHARON (AP) – A former Texas prison sergeant is slated to stand trial, accused of throwing a handcuffed prisoner onto a concrete floor so viciously that the inmate died. Lou Joffrion slammed inmate David Witt in August 2017 in an attack that was captured on video at the Darrington Unit in Rosharon, south of Houston. The Houston Chronicle reports that Joffrion will stand trial in September on an aggravated assault charge. State officials say Joffrion had just weeks before completed six months of disciplinary probation for another violent encounter with the 41-year-old Witt. Prison officials Monday condemned Joffrion’s conduct but noted a powerful painkiller in the slain inmate’s blood as a possible cause of the altercation. Officials didn’t report Witt’s death as a homicide until the full autopsy was completed a year later.