Deputy Sheriff is a police officer.
The Deputy Sheriff (as his plate says) is among other police cars, the ones who put the order in the routes. He is seen stopping Ramone and Fillmore because of Fillmore's organic fuel use on one section of the Route 66 in Oklahoma. Also, he is seen cutting the route because of some reports of the famous Tommy Triggertire speeding, which confuses with Boost, DJ, Wingo and Snot Rod. He is also the chief of the rest of the police cars.
The Deputy Sheriff only appears in the Boom! Studios comics.