I'm not sure people are giving her grief. Its very clear by the history of her coming to the force in light of this video that she is not fit to be a patrol officer and that many police officials have known she is not fit to be a patrol officer but continue to put her back on the street (she's back on the street again).I agree with that. She acted "unprofessional" because the guy wasn't listening and she had appear like she's a person who could make him comply through threats; and when he complied at first, she acted fine. I really don't see a problem there - I've seen even big male cops having to act tough at the get-go so the suspect would understand that the cops shouldn't be messed with...now, why are people giving this small female cop grief for doing the same thing?
I don't think she should be fired, but at the least she should be permanently pulled off patrol duty, not as punishment, but for the public safety. She isn't fit to do the job safely and professionally. Maybe she can handle some position in the jail, transporting prisoners, court security, or as a desk cop.