Legally, I don't' think it matters. The account holder of an internet connection is legally responsible for ALL things that go on with the use of it. Imagine if they started prosecuting people for sending out spam because they have an 'owned' Windows machine under the control of a botnet. Worse yet, what if the bot downloaded music without the user's knowledge, then they WOULD be screwed!
Similiar things are already going on. A teacher in New York, I believe, was prosecuted for exposing her students to porn and contributing to their delinquency when her school computer got spammed and she didn't know it happened or how to get rid of it. I think she lost her license, too.
Well I think this ruling is outrageous it is like you kid going to the store and shop lifting! They don’t through the parents in jail or fine them $25,000! The kid goes to juvenile detention center! No wonder nobody buys CD’s anymore and most of them have copy protection on them!!!!! I don’t buy them haven’t bought any in years!