Whenever there is an insert of either the radio, the "hot sheet" (list of stolen cars), or when Reed is jotting down information on the pad, the visuals almost never match the continuity of the scene. Example: It can be daytime in the scene, but when the insert of the radio or the hot sheet is shown, they appear, due to the lighting, that the inserts are from nighttime. Also, the same insert of Reed writing on the pad is used whenever he writes info down. As with the errors with the radio not matching the scene, there are times when Reed is wearing the short-sleeve uniform, yet when he's writing info down, we see the cuff of a long-sleeve shirt.
Invariably, Malloy hits the lights and siren *before* being instructed to respond "Code 3" to a call. While some may consider this inaccurate, given Malloy's experience and type of call, he would anticipate the call response as "code 3." This is normal in police and fire/medical responses.
By the end of the series, despite having been an LAPD officer for 7 years ( the amount of time the series was on air, and presumably real time ), Reed still doesn't have at least on service hash mark on his uniform sleeve indicating 5 years of service.
Depending upon the episode, the top middle knob for selecting the radio channel is missing.
In many shows a gold 1967 Mustang with a white vinyl top may be seen either parked at the crime scene or cruising the street in the background.
Throughout the run of the series, Malloy and Reed are found patrolling in many different divisions, such as Harbor, Van Nuys, Rampart, and so on. Since they are assigned to Central Division, that means many of the stories should take place in downtown LA, when only a handful seem to. Officers from one division do not randomly go patrolling in other divisions, as Malloy and Reed do.
In many instances where Malloy and Reed stop someone for a traffic violation and there is going to be a long dialogue scene between the officers and the offender(s), the driver will always get out an walk towards the officers. This is a gross violation in the law that at the very least would result in being cuffed for the duration of the traffic stop or result in an actual arrest because it is against the law for anyone to step out of the car and approach the officer unless otherwise instructed by the officer. This fact is verified by the two LAPD Academy instructors on the Season Two DVD Commentary.
In all episodes throughout the series, during any interior scenes showing the captain's office, which is depicted as having a door and windows facing the hallway and a wall with a window looking into the adjoining office, there is never any glass in either the doors or windows.
The radio being used in the early episodes has its squelch knob turned to its highest setting (clockwise). This would allow the radio to receive only the strongest of radio transmissions from dispatch or other cars. If they moved to a fringe area or were talking car-car, most likely nothing would be heard by them.
The police officer characters often take a position behind their police vehicle door in a shootout or potential shootout as a position of supposed protection. The police would not do so in real life as a vehicle door, police cruiser or not, would provide little protection from a gunshot, that is unless the door was reinforced which most police vehicle doors are not.
At the opening of every episode, the radio announcer makes a call to Adam-12 and reports some crime in progress. Adam-12 then speeds to the scene - without the benefit of the address.
Grievous police errors that could cost an officer their life were frequently committed by Malloy and Reed, whereby these supposed seasoned officers regularly turned their backs on perps, or allowed them to fetch and/or brandish guns without showing much of any care as to their own safety.
For all the "authenticity" Sharon Claaridge was supposed to bring to the part, police dispatchers simply do not ever say "see the man" when radioing a call.
Their blacks don't match! In many highly lit scenes---sun and interior lighting---it is clear that Malloy and Reed's uniforms aren't up to standard. Their shirts are a different color black than their pants and their ties much darker than the shirts. It's like they're wearing graphite pants, charcoal shirts and black ties.
Besides their uniforms being of different black colors, their guns are flopping in the wind---like streakers in the football field---whenever they run, as their holsters aren't sturdy enough to stay in place, nor secured to their hips like in more credible cop shows.