"I've realised there were a lot of situations that we went into that she was the reason I got out of there."
But this loyalty went further than just her work.
Asta was born on the same day as Fitzgerald's daughter and the two of them had shared a "real special link" that no one could match, he said.
He laughed as he said that she would always tell him to make sure the dog was brought home safe before worrying about him.
Asta had a good "on and off" switch meaning she knew when to be serious but also when she could play and be loving.
She could go from cuddling on the couch and mucking around with her chew toys to working alongside the Armed Offenders Squad and helping catch criminals.
"She is the queen of the house and the queen of the streets."
Fitzgerald had another police dog, a three-year-old male, who Asta is not a fan of.
"I can't let them out together. I've done it a few times and she pinned him to the ground. She is so dominant."
He said she was also not a fan of cats after their family cat "beat her up" as a puppy.