Steve Landesberg, an actor and comedian with a friendly and often deadpan manner who was best known for his role on the long-running sitcom “Barney Miller,” died in Los Angeles on Monday. He was 74.

Enlarge This Image

The cause was colon cancer, his daughter, Elizabeth, said.

On “Barney Miller,” which ran on ABC from 1975 to 1982, Mr. Landesberg played Sgt. Arthur P. Dietrich, an intellectual detective with a quiet manner who seemed to have an unrivaled knowledge of practically any topic that arose, much to the bewilderment of his fellow detectives.

He was also given to odd, unexpected pronouncements. In one 1980 episode he tells his boss, Captain Miller, played by Hal Linden, that he is working on a case that dates to 1973. Miller says: “That was seven years ago! Nixon was president!” Dietrich’s low-key response: “No, he’s got an airtight alibi for this one.”

Mr. Landesberg received three Emmy Award nominations for that role.

Set in a New York City police station, where most of the action takes place, “Barney Miller” portrayed a group of wisecracking detectives and the oddball characters who ended up there. Some police officers said the show represented the real life of rank-and-file officers better than many television detective dramas.

After “Barney Miller” left the air, Mr. Landesberg appeared on “The Golden Girls,” “Law & Order,” “That ’70s Show” and “Everybody Hates Chris,” among other shows. He had a recurring role on the short-lived 1998 sitcom “Conrad Bloom.” Most recently he played Dr. Myron Finkelstein, a Freudian therapist, in “Head Case,” a comedy on the Starz cable channel.

In 2008 he played a pediatrician whose patient (played byJason Segel, the film’s writer and star) is in his 20s in the hit movie “Forgetting Sarah Marshall.” His other movies include “Wild Hogs” and “Leader of the Band.” His distinctively dry, deep voice was also heard in cartoons and commercials.

Stephen Landesberg was born on Nov. 23, 1936, in the Bronx. He began his career as a stand-up comic in the late 1960s and became known for his off-center observations and eccentric delivery. He performed in New York comedy clubs alongside comedians like Freddie Prinze and Jimmie Walker.

Mr. Landesberg appeared on “The Tonight Show” for the first time in 1971 and several times on “The Dean Martin Show” before landing his first recurring role, as a Viennese violinist, on the sitcom “Paul Sand in Friends and Lovers,” in 1974.

Besides his daughter, he is survived by his wife, Nancy Ross Landesberg.

Initial reports of Mr. Landesberg’s death, relying on numerous biographical sources, said he was 65. In acknowledging that he was actually nine years older, his daughter said he had provided varying birth dates over the years. “He got kind of a late start in show business,” she explained, “so he tried to straddle the generations. He fooled the whole world. People were surprised to think he was even 65.”