The role of John Munch has been reprised on various “Law and Order” spin-offs and has become one of the longest running roles in television history. Playing Munch, Belzer appeared on Fox television’s “The X-Files”, HBO’s “The Wire”, and various other shows including "Arrested Development," "The Beat" and "30 Rock." In total, Belzer has played Munch in ten different shows. Belzer says of Munch: “The character of Munch was really close to how I do things. It was a dream come true for me and an utter delight to play this character for so many years. I’m very lucky.” Richard Belzer debuted the role in January 1993, with NBC's "Homicide: Life on the Street." Munch was even turned into a Muppet for Sesame Street to solve alphabet related crimes.

Belzer started his career by doing stand-up comedy at The Improv, Catch a Rising Star and Pips. He attended Dean College in Franklin, Massachusetts but was expelled. “I got thrown out of every school I ever went to for uncontrollable wit. I think comedy chose me.” Belzer performed with the Channel One satirical comedy group that became the basis for the cult movie “The Groove Tube”. 

He later entered the film industry, where he appeared in Café Flesh, Fame, Scarface and Night Shift. Belzer contributed to radio too, he was a featured player alongside Chevy Chase, John Belushi, Gilda Radner, and Bill Murray for the National Lampoon Radio Hour and was also the warm up comedian for Saturday Night Live.  Belzer has also been a frequent guest on The Howard Stern Show.

He has good experience in television also; he worked regularly on the show called The Flash. He can be viewed in several episodes of The New adventures of Superman. He played in Homicide: Life on the Street, Orbach: Law and Order and Law & Order: Special Victims Unit.

Belzer has many different types of experiences throughout his lifetime. Some of the major events, fact and notable things are presented as follows: he worked as a paper boy when he was youth in Bridgeport, Connecticut, then he started to work as a reporter for the Bridgeport post as well as several other newspapers. He became teacher, a jewelry worker, a dockworker and a census-taker before entering into the entertainment industry.

Hulk Hogan hurt Belzer and he went unconscious and was hospitalized and, for which, Belzer sued Hulk for five million dollars. On July 30, 2014, his older brother killed himself by jumping from his 16th floor apartment in New York City. Richard Belzer is a cousin of Henry Winkler and speaks French fluently. In 1984, he suffered from testicular cancer. George Carlin, Chevy Chase and Richard Lewis are his friends.