How to catch a cracker in the US?

Wed Mar 12 10:10:27 UTC 2014

> From: Dobbins, Roland [mailto:rdobbins at arbor.net]
> Sent: Tuesday, March 11, 2014 8:06 AM
> Although it's questionable whether or not it's possible to remotely absolutely
> ascertain whether the attacking machine in question was being operated by
> miscreants unbeknownst to its actual owner.

Though it's 100% correct would this withstand in the court? 
e.g. nope wasn't me downloading that movie, must have been a hacker misusing my PC, I didn't even know there's a "torrent client" as you guys call it installed on my PC I only use it to play solitaire. 