Richard Belzer is leaving \"Law & Order: Special Victims Unit,\" the New York police drama on which he has played Sgt. John Munch for 15 years. Munch put in his retirement papers on Wednesday\'s episode of the show. Next week\'s installment is expected to be about his retirement party, UsMagazine.com reported. Belzer, 69, originated the role of Munch in 1993 on NBC\'s \"Homicide: Life on the Street.\" The iconic cop character also appeared on \"The X Files,\" \"The Beat,\" \"Law & Order\" and \"Law & Order: Trial By Jury.\"