Tick
Senior Member
The only thing of real concern is child abusers / pornographers, most the other so-called "concerns" are victimless crimes. There are many methods authorities use to catch perpetrators - the Internet doesn't prevent you from doing "good old-fashioned police work". One common effective method is employing undercover agents to infiltrate groups trading child porn or who attempt to lure pedophiles. Other more sophisticated methods include advanced data-mining / aggregation techniques, like the techniques used to catch members of Anonymous (it's worth reading up more on this, some very interesting technical forensic techniques). Then another "old-fashioned" technique was used - after they caught one guy, they set up a deal that he would secretly work undercover for authorities as an informer (in exchange for lighter sentencing), allowing them to gather lots of info about the rest of the team who were then later arrested.
The reality is it's already (for all practical purposes) nearly impossible to be truly anonymous on the Internet. If even Anonymous got busted, the ordinary person can pretty much forget about it. The reason most hackers don't get caught is because most the stuff they do (e.g. website defacements) are so petty it's not worth spending time on.
On the one forum they were discussing how burning the victim after the rape is the best way to get rid of evidence. The other dude was telling people how aroused he got looking at kids in the mall but he'll never act on it.