I could give you a full breakdown of how it works in EU, but basically there needs to be indisputable evidence that a crime occured for any party to subpoena any ISP or service provider company. Otherwise those companies will be in huge trouble. The one doing the subpoena because they wouldn't have an order for that and if they fuck around right before suing, courts will not take kindly to that. And the other receiving the subpoena for disclosing personal information (although they'd maybe win a defense to that, because if they did their due diligence they are not supposed to tank the damages).

What I'm saying is, considering currently laws in the EU, I think we're good. Of course IANAL so ask one if you need specific advice.