Contrasting Attitudes
In the Dragnet episode, The Interrogation, Internal Affairs officers Friday and Gannon question Officer Paul Culver about his being a suspect in a liquor store robbery. Friday tells Culver that his being a police officer has no bearing on the investigation because he fits the description and was in the area when the store was robbed.
Contrast this with the Adam-12 episode where Mac has his one-of-a-kind, made especially for him in Mexico, cowboy boots stolen. Malloy and Reed spot a guy wearing those exact same cowboy boots. They think they have their thief, until he shows them his badge and ID revealing him to be a fellow LA cop. Malloy immediately decides that he isn't the thief and explains that their supervisor had his boots stolen and that Mac thought the boots were made only for him.
Interesting for the contrast in attitudes of the officers involved. For Friday and Gannon, being a cop gave you no special treatment, but for Reed and Malloy, being a cop automatically made the guy innocent.