But when the Edmonton police dog was stabbed to death last fall, Williamson's six-year-old daughter started to ponder the real dangers of the work.
Crying, she went to her dad one day with a question.
"'If Quanto's job was to protect you from bad guys ... is a bad guy going to kill you?'" Williamson recalled in a victim impact statement read in court.
"She now never lets me leave for work without a hug."
The man who killed the dog, Paul Vukmanich, pleaded guilty Tuesday to six charges, including animal cruelty and flight from police.
Crown and defence lawyers both recommended he get 26 months in jail. A judge is to sentence him Friday.
Court heard the 27-year-old was on parole and high on cocaine and methamphetamine when he got caught driving a car with stolen plates on Oct. 7. When police tried to pull him over, he sped over a median and several curbs, sent sparks flying and blew out three tires.
He abandoned the car in a parking lot, then took off on foot.
Williamson warned him to stop or he'd send his German shepherd out. Vukmanich slowed down but refused to get on the ground. Instead, he backed away in a fighting stance.
Quanto was set loose and bit Vukmanich on the left arm and hand. Court was told Vukmanich pulled out a knife and started stabbing the dog in the chest.
Williamson pulled his pistol and ordered the man several times to drop the knife. Other officers also yelled at Vukmanich to stop.
At some point, Vukmanich dropped the weapon and Williamson ran over and picked up his dog.
"Quanto's legs began to fail and then his head fell," said Crown prosecutor Christian Lim. "The officer carried the dog back to the truck with blood streaming out from it all over the officer."
Williamson rushed the dog to a veterinarian, but it was too late.
In addition to jail, lawyers agreed Vukmanich should be banned from owning a pet for at least 25 years and be prohibited from driving for five. He had previously received a lifetime ban from possessing weapons.
Lim also asked Vukmanich be ordered to pay $40,000 to the police force to cover the cost of a new police dog and its training.
Judge Larry Anderson said he would consider the request, although he said it sounded to him more like a civil claim.
He also said he wasn't sure a 26-month sentence is long enough, since Vukmanich has a criminal record that includes two prior convictions for evading police.
"I am troubled, frankly," said Anderson. "I want to think it through carefully."
Officers complained after Quanto died that the strongest criminal charge that could be laid was cruelty to an animal.
The federal government said in its fall throne speech that it plans to bring forward "Quanto's Law" to protect police animals, but didn't specify what that might entail.
Williamson was in Ottawa when the announcement was made.
He wrote in his court statement that Quanto was like a pet to the Williamson family, but knew his primary role was as protector.
"I always knew if it was him or me, it would be him," Williamson said.
"Quanto died well and proved his fearlessness."
Williamson said he is to start training a new dog soon and will rejoin the canine unit in the spring.
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