It made perfect sense that a dog, temporarily pressed into the service of the law, would present for the audience the characters of a beakless duck and an angry Japanese mouse.
I have a dim memory of Hashimoto, and this explains it: “Between 1963 and 1965 the shorts were incorporated into The Hector Heathcote Show as part of NBC's Saturday morning cartoon lineup.” Ah, yes. Hector Heathcote. One of those things kids watched because it was on. And for no other reason.