In Pixar's Cars, the legendary racer who serves as Radiator Springs' judge is Doc Hudson.
Doc is introduced as the town's experienced local physician, but the story reveals that he was once the Fabulous Hudson Hornet, a celebrated racing champion. He judges Lightning McQueen's community-service sentence after Lightning damages Radiator Springs' main road.
Doc's history explains his initial hostility toward professional racing. A crash ended his competitive career, and he felt that the racing world had moved on without respecting what he had accomplished. Lightning's arrival gradually changes Doc's outlook, while Doc becomes an important mentor to the younger racer.
Paul Newman voices Doc Hudson, making the character especially notable because Newman was both an acclaimed actor and a real racing enthusiast. The character is inspired by the Hudson Hornet, a genuine automobile associated with early NASCAR success, although Doc himself is fictional.