Visible crew/equipment: When Pat and Tiffany arrive at the hotel for the dance competition, in the first shot inside the building, the camera is shown moving forward towards them. To the left of shot, the reflection of the camera and cameraman can be seen in the glass window. (01:38:48)
Continuity mistake: Deniro starts taking off his jacket at the dance competition and it's halfway off his left shoulder. In the next shot his jacket is back on.
Continuity mistake: When Tiffany meets up with the family at his home and they're discussing football, she's drinking a Bud, then after an angle change she is standing with her arms folded.
Continuity mistake: When Veronica takes Pat and Tiffany on a tour of her house, she bends down to light her fireplace and on the left you can see an iPod in the wall-mounted iPod dock. A little after this, she shows them the dock, and it is empty again.
Continuity mistake: In the scene where Tiffany is attempting to put a full length tie on Pat for the dance competition, Pat's collar is up and down inconsistently.
Continuity mistake: At the end of the dance competition, Pat hugs Tiffany and starts walking towards Nikki. After he reaches where she is standing in the close-up shot, the subsequent distant shot which follows shows him still approaching her.
Answer: It's not exactly common, but yes, it would be up to the judge, and establishing that a person is a "clear and present danger to themselves or others" can result in involuntary commitment in Pennsylvania, where the film takes place. In this case, it would not be hard to argue that, "the person has inflicted or attempted to inflict serious bodily harm on another and that there is a reasonable probability that such conduct will be repeated" (50 PA. CONS. STAT. ANN. ยง 7301 (b) (1)), as he had just physically assaulted his wife's lover and she'd obtained a restraining order. His mental health problems would have been well-documented, so it would have been easy for a judge to order him to undergo psychiatric evaluation, which could (and, in the film, does) lead to extended involuntary commitment at the discretion of a mental health professional.