Ned Jordan is an agent for an unspecified agency.
I have seen a reference that mentions he works for the FBI but I am more inclined to believe that guesswork on the part of the article writer than anything else. What is known comes to us from the announcer of his adventures.
To the sound of a train moving down the tracks, the voice of the announcer tells us, "Speeding from coast to coast, the Federal Express thunders through the night. Adventure, thrills, romance. Ride the rails with Ned Jordan, Secret Agent".
He goes on to inform the listener, "Under the guise of settling labor and accident claims for the Consolidated American Railroad, Ned Jordan secretly investigates the activities of foreign agents and other federal enemies - missions known only J.B. Medwick, president of the railroad. Government agents act on the information gathered by Jordan, who steps quietly out of the picture".
Now that would lead one to believe that Jordan was more of a private investigator than a government operative but that is contradicted, in my opinion, by Jordan when he is able to call upon federal authorities to aid in one of the missions; a private citizen would not have been afforded such accommodations.
Whatever department, agency, or bureau he worked for, Jordan, from the couple of adventures we still have of him, was an energetic, action-loving operative who relished the danger that comes from hunting down and confronting foreign spies and saboteurs.
In the one episode I was able to get hold of, Jordan worked with a woman named Judy who, while probably not an agent herself (considering the era), was definitely capable and interested enough to be one and deported herself extremely well, enough to make me wish I could learn more.