According to the Hollywood Reporter, after a protracted struggle with diabetes and end-stage renal failure, according to his wife Carole Raphaelle Davis and friend and former assistant Jay Mandyam. Rooney had reached age 71. Veteran stand-up comedian Rooney earned two Emmys for writing on HBO's Dennis Miller Live in 1994 and 1995. He also worked with Jay Leno and coached Judd Apatow and other emerging comics.

After accidentally making his stand-up debut in 1977 at El Brookman's in Washington, D.C., where he had a pitcher of beer poured on his head, Rooney returned to stand-up comedy, first in New York City and then in Los Angeles, where he became a regular at the Improv comedy club and met Leno, according to a notice submitted by Mandyam.