I'm not naive about dogs. I've had GSD for 28 years of marriage and about 30 years before that.
I've been bitten once by my GSD because I was young and stupid. She was about 1 year old and chewed up my good cowboy boot. I got pissed and swatted the crap out of her and she saw me raise my hand and stopped me by clamping on briefly. I was shocked by how fast and how hard she clamped down.
I calmed down, she backed off and I just realized that I was the wrong one and she was scared. We were friends for 12 years and I respected her after that and learned what a crappy dog owner I was till I started to train myself and my dogs.
An officer has to want to be K9 and apply for and qualify for specifically
Less likely to be a dog beater