Well...nothing can be guranteed on anything..the cops are also humans...they too are prone to errors....it is just that cops are demanded by any society not to make huge blunders therefore they are given far resource and tools necessary to cut down those potential errors. Hey by the way, I have been confronted by cops three times here (for taking pics of people being arrested on street by cops) and in one instance they even (indirectly) demanded not to publish photos anywhere. But from these experiences what I figured out is the fact that these cops are far more nervous than we are and far more scared about being the victim of their own potential blunders. Anyway, in this case no court will see the undercover works of cops as anything degratory to either the defendant nor the cops themselves. By the way cops are far outnumbered when it is compared with potiential sex offender that are lurking over the internet looking for their victims. This is small victory for cops against these creeps but still it is a victory. It is not just a matter of law...it is an uncomprehensible and disgusting thing to try to sexually exploit immature and young kids.