Dennis Franz was born Dennis Franz Schlacta in Maywood, Illinois, a suburb of Chicago. His father was a German immigrant and both he and Franz's mother, were postal workers. He has two sisters, Marlene (born 1938) and Heidi (born 1935). He graduated from Southern Illinois University and was immediately drafted into the military. He served 11 month in Vietnam in a reconnaissance unit, and after his service he suffered depression for some time afterwards. In 1972 he joined the Organic Theatre Company. Robert Altman discovered him at an auditions and urged him to go to Los Angeles, where he became part of Altman's resident company. He married the former Joanie Zeck in 1982 and has aided her in raising her two daughters, Krista (born 1976) and Tricia (born 1974).


Before entering "Hill Street Blues" (1981), as Norm Buntz, appeared as Sal Benedetto for a few episodes. Always travels with a pet bird. Served 11 months in Vietnam with the 82nd and 101st Airborne divisions. Franz's own recipes are included in "The Cop Cookbook" by Greta Garner-Hewitt, Ken Beck and Jim Clark, published in 1997. By 11th grade, he tried out for a part in a school play called, "The Crucible," because his girlfriend was auditioning. He won the part, but his girlfriend didn't Is a board member of the National Colorectal Cancer Research Alliance Was a mailman before becoming an actor He and Jimmy Smits began their association with Steven Bochco in the 1980s. His former "NYPD Blue" (1993) co-star, David Caruso, is currently the star of "CSI: Miami" (2002), the spin-off of William Petersen's series "CSI: Crime Scene Investigation" (2000). Franz and Petersen co-presented an award at the 2004 Emmys. He was nominated for a 1976 Joseph Jefferson Award for Actor in a Principal Role in a Play for "Switch Bitch" at the Organic Theater Company in Chicago, Illinois. Was considered for the role of Vic in American Graffiti (1973).