The Joker's Bus Driver

The Joker's bus driver was an accomplice of the Joker during the robbing of Gotham National Bank.

History
This man earlier stole a school bus to use as the getaway bus under Joker's secret orders, presumably so they could disguise themselves within the line of School buses as they are headed home. He then ran the school bus into Grumpy, accidentally killing him. A moment later, after the money was loaded onto the bus, he looked around confused and asked "Bozo", who was the Joker, "What happened to the rest of the guys?", where upon the Joker shot him dead with his machine pistol.

Behind the scenes

 * It is currently unknown if the Bus Driver had a callsign like the rest of the thugs involved in the robbery. One possibility is that like three of the others, (Grumpy, Happy, and Dopey), he may have taken his name from one of the Dwarfs in Snow White and the Seven Dwarfs. The four unused names were Doc, Sleepy, Sneezy, and Bashful.

Another possibility is that he took a name from a fictional clown character, as with Bozo, and Chuckles. This could range anywhere from Clarabell, to Ronald, to Krusty.

Going by his last statement before Bozo/The Joker gunned him down, the Bus Driver was apparently not let in on the backstabbing plan.