Continuity mistake: When Halle starts screaming while busting through the barricades, her windshield cracks on the lower driver's side. After the car stops there's no crack anymore. (01:04:40)
Continuity mistake: At the beginning of the movie when Halle Barry is talking with her husband in his office, every time a shot cuts to him sitting at his desk, the way items are arranged on the desk changes.
Continuity mistake: When Miranda (Berry) took the guard's car and skidded to a stop by the sinkhole the front passenger wheel was angled toward the driver. A few shots later as the camera pans away from the car the wheel is straight. (01:05:00)
Continuity mistake: In the scene where Miranda escapes and goes back to her house, we see flashbacks to her husband's murder, including one of Miranda in the bathtub filled with water stained red from blood. When the flashback ends and we return to the present, the tub is spotless, even though there should be at least remains of blood there.
Answer: Plain and simple, it's bad script writing and there's a number of other examples of "that wouldn't happen in the real world" that unfortunately we're suppose to accept. Although, if one had to justify it, you could say; when Miranda was in the hospital, she had not been tried and convicted yet, so when her trial did occur, Miranda's lawyers did not use the "I was possessed" defense and was found not guilty because of reasonable doubt. Or the DA's office made a deal with her because she was a high standing member in the community who exposed a number of issues and may have gotten parole instead of jail time. And Chloe was Miranda's patient before she herself was admitted to the psychiatric ward. At that time, Miranda never believed Chloe was anything but delusional and after spending time in the hospital as an inmate, she believed her and once she was free, she worked on getting Chloe released by stating she was not insane.
Bishop73