Sometimes police go undercover to apprehend people who sell drugs, disguise themselves as prostitutes to catch people in the act, or pose as children online to catch pedophiles and predators... Do you believe this to be necessary or do you think it is simply entrapment? Do you believe that this is a legitimate legal strategy? Why or Why not?

In a lot of cases yeah,cause the people they are going undercover to catch are criminals and if they walked up in a uniform the perp would run like crazy.

I believe that it is absolutely necessary.. because the observer, changes the behavior of the observed.

Look at reality tv shows, I have no doubt in my mind, that some of the strange behavior seen on camera, is due to the fact that the person acting strangely, knows that he or she will be seen by others... sometimes that strange behavior is coerced.. (i.e. the Jerry Springer show, and shows like Blind Date, or Elimidate, etc..) but, in that instance, it becomes painfully obvious.

If a person shoplifts from a store, then it is likely due to the fact they thought that no one was watching them, and that they'd get away with it.. but if they know that there are cameras, because signs have been posted throughout the store, then the likelihood of that person shoplifting, will be a lot less.. (mind you, this is not taking into account the level of that person's stupidity, or mental and behavioral disorders such as kleptomania..)

People will act a lot different than they would normally, if they know that they are being watched.

That said, the only way you can truly catch someone in the act of doing something wrong or out of the ordinary, is to catch them by surprise.

well your right is to catch them by surprise but what if they knew about it they wont be catched easily and know how to take care of it