I actually went back and watched Dear Boy, and the way she responds to Gunn is really horrible.
It is, and I think that scene was a comment from the writers on the racism which seems to be endemic in a lot of police forces, particularly the LAPD. She's not a bad cop, but she reacts in that manner when confronted with a young black man. Admittedly she was under a lot of stress at that moment and perhaps not as in control as she should normally be.