Baltz was born in New York City, New York. He is best known for his role as Officer Marvin Nash, an LAPD police officer in the famous torture scene of the 1992 Quentin Tarantino film Reservoir Dogs. Baltz also starred in another film written by Tarantino, 1994's Natural Born Killers, as Roger. His other film credits include the 1990 drama film Dances With Wolves, the 1997 action film Face/Off and the 1998 political satire Bulworth. Notably, Baltz starred in Paul Thomas Anderson's directorial debut in the 1993 short film Cigarettes & Coffee.
Baltz has appeared in many made-for-television films, and starred in the 1999 miniseries To Serve and Protect. He starred in the short-lived 1992 television series Human Target, and played sinister stalker Steve Roth in The Marla Hanson Story (1991).
