As the warden had stated in the movie, Miss Dice is the head of security. If that were indeed true, she would been strictly in a bureaucratic role and not allowed to perform prison guard duties, including the handling of a weapon and certainly not while wearing pumps and a skirt, for obvious safety reasons.
When Laurie kicks China in the face and knocks her backwards into the pool, seconds later after falling in, China's body assumes the 'dead man's float' position. This would not happen immediately after death unless she went into the water face first or sank to the bottom and resurfaced after her lungs filled with water. She went in on her back, stayed at the surface and her body changed positions immediately.
While for-profit prisons are not unusual, states that use them typically only do so for minimum security facilities. It is highly unlikely that any state's department of corrections would tolerate so many incidents of violence at a single facility, and would have likely pulled the contract and staffed it with state employees.
As Laurie had stolen and destroyed his car, Judge Waters would have been called as a prosecution witness at her trial. No court would ever allow him to preside in this circumstance.
After the judge pronounces Bonnie's sentence, he gets up from the bench with adjourning court.
After Laurie releases her foot from Kay's neck and flees, Kay gets up and her voice is heard screaming as he pursues Laurie, but her mouth doesn't move.