Okay, let me clarify the situation somewhat. The teacher did not call the cop. THAT is why I say the teacher did the right thing. The teacher tried to get the disruptive student to put the phone away, and the girl went on being an ass. Teacher asked her to leave the room, girl refused. Teacher contacted administrator, (assistant vice principal I think) asked her to come into the hallway, girl refused. Administrator contacted the officer.
Also, officer did not have a "reputation" for violence. The two complaints were from his rookie year 8 years earlier, and not substantiated, according to some sources (the Department has not confirmed).
I agree that having cops in schools can, and does, change the dynamics of the schools, and leads to escalations in enforcement. This is something that should have been handled "after class" (depending on how disruptive she was being). Her refusal to stop being an ass is what led to the confrontation. But, she could have been removed after school.