He was born on September 12, 1950 in Manhattan, New York City..
In 1977, Mahler appeared on two episodes of the TV series, Fernwood 2 Night. In 1980, he appeared on Fridays, an early 1980s Sketch show on ABC modeled after NBC's Saturday Night Live, where most of Mahler's appearances showcased his musical talent and radio DJ-style voice, most notably in the recurring sketches "The Latin DJ" and the one-off sketches "K.P.L.O" (about Palestine Liberation Organization terrorists hosting a radio show in their bunker) and "A Classical Get-Down" (about a classical Pianist who hosts his radio show like a Top 40 station).
Two years after Fridays was cancelled, Mahler portrayed Sgt. Douglas Fackler in the 1984 film Police Academy. Other film work included 1984's Friday the 13th: The Final Chapter, the 1985 sequel Police Academy 2: Their First Assignment, the American sitcom Diff'rent Strokes, 1986's Police Academy 3: Back in Training, 1987's Funland, and the 1989 sequel Police Academy 6: City Under Siege.
In the 1990s, appeared on the television series The Famous Teddy Z and had a recurring role on Seinfeld. Bruce had minor roles in the movies Hook, Dick Tracy, and Loaded Weapon 1. Through 1995–1998, Mahler starred as a rabbi who Elaine befriends on the Seinfeld episodes "The Postponement", a deleted scene in "The Hot Tub", "The Serenity Now", and "The Finale".
