[Saracen]

One thing people need to realise is that what's being proposed here is not a prosecution, and it does NOT need courtroom standards of proof. It may be that a court would throw out a case if it couldn't be proven who was downloading over an account, but I've yet to see an ISP that doesn't have account terms with a prohibition against using their services for illegal means.

Make no mistake, ISPs can disconnect you if you breach those terms. And, by and large, it'll be your responsibility to see that your account isn't abused, even if that means securing your wireless link. If you don't, and if illegal activity results, they'll simply invoke that contract term and cancel the account, if they wish to do so. Whether they have a standard of proof that would satisfy a criminal court that it was YOU doing it is irrelevant - it was on your account.

ISPs no doubt won't want to lose customers, but if the alternative is to face a legal battle that might well cost hundreds of thousands, well, they may just take the pragmatic approach and lose a few customers.