This is drawn loosely from the childhood of series creator Steve Franks, who was also born into a family of police officers and whose father "was training [Franks] in his own way to follow his footsteps." Franks' father would ask him how many people were wearing hats in a restaurant, a tactic Henry employs in the series pilot.
This is inspired by the childhood of Steve Franks, creator of the show, who was raised in a family of police officers and whose father instilled in him a love for law enforcement. The father would often ask Franks to count how many people were wearing hats in a restaurant, a tactic that Henry uses in the pilot episode.