"Get 'em, boy!" - Trooper Thompson, urging Peanut Butter on to chase down fleeing criminals.
Peanut Butter, just like his colleague Duke, underwent the same training every Police K9 undergoes. Upon graduating from the 'academy', he was put under the care of Eli Thompson.
Like the other dog on the force, Peanut Butter developed a bond with Trooper Thompson that created a sort of 'telepathic communication' between the two, only being able to speak like the average human to his handler and understood by such.
And, due to that laid back bond, the two occasionally bicker and have casually conversations on patrol.