State Trooper spent three seasons in syndication (winter 1957-June 1959) after NBC passed on the series. The pilot had aired on Campbell Star Stage in 1956.
Rod Cameron top-lined as Lt. Rod Blake, and introduced & closed each episode, while providing narration in-between, the latter marking the series as a knockoff of Dragnet. It was a standard crime drama of the era, but that genre was growing toward the end of the 50's, and that might explain why NBC, as well as CBS & ABC, passed on the series, leaving it open for the fertile ground of syndication.
Let's take a look at the opener, "The Red Badge of Death":