Ernie was the Joker 's henchman and an antagonist in The New Batman Adventures.
Ernie was hired by the Joker to be his chaffeur and accountant after he recieved 250 million dollars from King Barlowe. He helped the Joker recruit a new henchgirl to replace Harley Quinn . When the Clown Prince of Crime found out most of the money is fake, he decides to commit a robbery without his trademark gadgets to reclaim his fortune. To make sure that no one will notice his absence, the Joker had Ernie dress up as him at the Iceberg Lounge to provide a false alibi. Bruce Wayne saw through Ernie's disguise and flushed the information from him as Batman.