Basically in my story, a cop is on patrol and he spots some suspicious activity. He sees in the distance, a man being searched by other men for a wire and possible weapons. Or at least that is what it looks like from his police knowledge. So he decides to discretely follow them in his unmarked car, keeping his distance. The man who was searched is a dirty cop, and the gang members who searched him are taking him for a blood in. A blood in, is when a gang puts new recruit to the test where the new recruit has to spill the blood of another person to get in. The cops sees his happening and intervenes, stopping the blood in. He saves the would be victim of the blood in, and manages to arrest one of the gang members, holding him at gunpoint while protecting the victim. The other gang members get away, including the crooked cop. The crooked cop then makes his way to his car, which was parked back where he was searched. He changes his clothes and his appearance, putting the clothes he was spotted in by the cop, in his car trunk. Or he does something along these lines. He then gets in his car, and drives to the crime scene. He has his police radio with him while off duty, and acts as though he is responding to the crime, as himself, as an officer, while off duty. So he goes to the scene as back up. But he only does this to see if he can control anything at the scene, such as his possible DNA being there something. He also wants to find out how the blood in was busted, and what the cop saw and all that, and this gives him a reason to, for the time being, be on the case and find out more, so he can know what he and the gang are up against. He doesn't of course fully realize that that the other cop, randomly stumbled upon it. However, I want to write this so it is believable. Is it believable that a cop, can see a man in the distance being searched, and then see him again as part of a blood in, in the distance, but then a few minutes later, that same man returns a car, with a different appearance, as a cop, who also works in the same department as the other cop? The two cops can of course work very different shifts, and would not have encountered each other directly before, but is possible to fool the cop this way, even though he didn't see the man from his face point of view?