He resigned from Pan Am in 1948 to pursue writing. The practical first step was the LAPD: he joined the Los Angeles Police Department in 1949, initially working in traffic and then moving into the department’s public affairs work. His police writing led directly to his first television work. The *Dragnet* television series was drawing on real LAPD cases, and Roddenberry served as the department’s liaison to the production, turning case files into story treatments. He was writing for television before he had an official writing credit.
He wrote under the pseudonym “Robert Wesley” in the early 1950s, contributing to multiple series including *Mr. District Attorney* and *Highway Patrol*. His freelance writing expanded through the 1950s to include *Have Gun – Will Travel*, *Bat Masterson*, and other Western series. His *Have Gun – Will Travel* episode “Helen of Abajinian” won a Writers Guild of America award in 1958 — the first significant professional recognition of his writing.
He resigned from the LAPD in 1956 to write full time. The next phase of his career involved producing as well as writing. He became a producer for the first time on the summer series *Wrangler* and developed several pilots that were not picked up by networks. The failures were instructive: they taught him the gap between what he wanted to make and what networks were willing to fund, a gap that he would spend the next decade trying to close.
The show that most directly preceded *Star Trek* was *The Lieutenant*, a drama about a Marine Corps officer that aired on NBC from 1963 to 1964. The show was not a success in ratings terms, but it was important for two reasons. First, it established Roddenberry as a producer who could get a show on the air and keep it there for a season. Second, it showed his willingness to use genre television as a vehicle for themes — including, in *The Lieutenant*, civil rights storylines — that conventional television was reluctant to address directly. The civil rights content led to friction with the Department of Defense, which had been providing equipment and cooperation for the show and withdrew support when the content became politically uncomfortable. This experience — of using the genre frame to address the uncomfortable directly — would become the defining strategy of *Star Trek*.