Murder, Robbery, E.T.C just to keep their cover?
Of course. Buying and selling drugs is illegal, but undercover cops do it often.
Technically, no. Any officer who violates the law to preserve cover is subject to prosecution for that violation. The badge is not a license to do anything illegal - on the contrary, police have less freedom than citizens, not more, and fewer civil rights if under suspicion, for department disciplinary rules are guilty until proven innocent. In real life, undercover officers must simulate rather than commit actual crimes, which is what makes real undercover work so unlike the fiction one sees in TV dramas. Past police corruption scandals have often involved cops who lived their covers so well that they changed sides, and joined the crooks. For one thing, the pay is much better, and for another, an undercover cop is not watched very closely by the overt cops, in order to not break the cover. The opportunity is great, the temptation is great, and the threat to one's life from associating with criminals whom one intends to betray puts on a lot of pressure. Nonetheless, the really successful undercover officers manage to penetrate criminal rings without actually participating in any crimes.
To a certain extent, yes, but there are very stringent limits on this. For minor undercover operations (e.g. posing as a street dealer to catch buyers), it's not normally an issue, but for major, long-term operations, it often is. Undercover officers often have to be present at, and participate, in some illegal activities to maintain their cover, and the authorities recognise this as part of the job. Undercover officers usually need to get special dispensation to do this, usually from whatever authority sanctioned the operation in the first place. There are some crimes, though, that are completely off-limits, and cannot be done. Murder is one of these; other very serious crimes, particularly those that involve assaulting or injuring someone, are also generally prohibited. To use a real-life example: in the Donnie Brasco case, an undercover FBI agent was able to infiltrate the mafia and spent years working with them. In that time he witnessed a lot of serious crimes, such as drug trafficking, and had to appear to be a part of it. However, eventually, the mafia trusted him so much that they decided to officially induct him into the mafia- this involved a requirement that he kill someone. As the FBI couldn't allow someone to commit murder, the operation had to be cancelled (although by that point they had evidence against hundreds of mafiosi).
NO Buying or selling drugs, or lets say setting up a deal to do so is what is called ENTRAPMENT vs ENTICEMENT. Murder as a part of a Gang Cult to keep your cover is not allowed as a BLOOD IN BLOOD OUT MOTTO. I have known many undercover officers, who went to bend the line, as being a member, being tested, then became inventive about being asked to kill someone, get the person aside and tell them what's going down, keep quiet, play along with them for the HIT on them, call this number for a safe haven after I supposedly kill you. shoot into the ground and walk away as DONE. There is a fine line of being inventive about doing so called illegal activity.
