I don't think many people realise the way pupils at some schools run the teachers ragged. For example, I have seen pupils know they can get away with:
-deliberately steaming into teachers in the corridor;
-throwing items/spitting at the teacher whenever he/she turns their back on the class for a second ;
-swearing profusely at teachers and taunting them (knowing parents won't care and detentions won't be served);
- pupils blocking the teachers' way and refusing to move, or pupils pushing past teachers to leave the room;
- pupils swearing at each other or fighting in the classroom;
-damaging/trashing property such as books, laptops, doors, cupboards.
Of course there are many good schools, many pupils who are a pleasure to teach and many supportive parents, but in my experience many teachers will regularly experience the above aggressive, loutish behaviour at some stage in the day.
The extra powers that teachers may get won't make any significant difference- it's all gone too far now.