Actually, that pretty much depends on the country. E.g Germany does not have the so called "fruit of the poisonus tree" doctrine. Therefore, the data uncouvered by Anonymus is viable to be used in a prosecution (well, there are some complications as validity etc, but those are with every piece of advise).

And if there are any Germans on that list, they will get prosecuted and probably punished.

Addtionally, you wouldn't believer how much resources are put aside in law enforcement for the tracking of child porn consumers. Round about none, law enforcement agencies tend to go after the "big fishes" so to say. The people in the movies, the distributers.

While there are sometimes bigger stings on consumers, they are more or less PR and negatibe general deterrence/prevention.

Therefore, while I'm not a big fan on neither vigilantism nor Anonymus, they did good.

That last sentence has just blown my mind with triple negatives (not..neither...nor) :).

However it's not just that the information was obtained illegally, the added defence I would expect it has granted in any fair court is that the people obtaining the evidence are fully capable and perhaps likely to tamper and inject evidence in order to implicate an enemy who is in fact not guilty of this crime.

Nice.

I don't know either, but considering official numbers and those of the human watch groups, plus all the shit that goes under the radar, it's proving to be very easy. It might be stereotypical, but a wealthy and influential group working in a corrupt state with stone age doctrines towards child protection has all the leverage it needs. And personal pleasure aside, the demand from the developed world also brings momentary gain. You have to target that, and you have to let them know that you're always watching. Internet vigilantes fit the bill somewhat. But their main purpose is to make themselves feel better about themselves, since you're not only watching that 2 year old girl getting run over, you're jumping on the truck driver with a knife before it hits her. The effectiveness of this is... questionable, of course.

Yeah, it was more clunky as intended ;)

I understand excactly what you mean, let me break it down:

it's not just that the information was obtained illegally

That is a problem in countries with the aforementioned "Fruit of the poisonous tree" evidence doctrine. The US "invented" it, I don't know the stance of the UK. But that fact alone doesn't necessarily mean that the evidence is unusable in court. And don't quote me on this, but I'm willing to bet that more than a third of all evidence obtained by the state in "big cases" (e.g. organized crime, terrorism) is obtained ilegally. It's just easier to cheat the system if you are in the system.

that the people obtaining the evidence are fully capable and perhaps likely to tamper and inject evidence in order to implicate an enemy who is in fact not guilty of this crime

This is an excellent point. But it's not like that this is only possible because anonymus provided the evidence. Actually, one of the biggest cases in recent history in Germany failed because excactly of that. We tried to ban a Neo-Nazi political party because their actions were unconstitutional. But during the process it emerged that some of the leading officials of that party were in fact informants for the german police. And because it couldn't be excluded, that the unconstitutional actions were orchastrated by the police (they actually did stuff like that before) the case was dismissed.

What I'm trying to say is, that only because Anonymus brought this evidence forward, it isn't worse than most state provided evidence. At least in Germany that is.

And concering that only "consumers" were targeted (afaik), they did more good than they might have done bad. But vigilantism tends to do more harm than good, therefore I generally share your opinion. But not in this case :P