said by CWO333 
:said by BonezX :because if at the time it wasn't law then it falls onto the situation of how can i do a crime when it was legal when i did it. ?
And that falls into the protection you get from the United States Constitution here in the US. Its called an Ex Post Facto law. Basically stating that if it was legal when you did it, you can't be punished for it if it becomes illegal later as long as you stopped doing it when it became illegal.
But when was copyright violation ever _legal_??? Sorry, that's just silly.
