Torrenting and illegal downloading files.?

Generally speaking, I don't believe the Federal Government combs the Internet directly for infringing content, so it usually falls to groups like the RIAA and MPAA to hunt down people whom they suspect are pirating. As it stands, you can be prosecuted for downloading within a certain timeframe. I don't know what they are specifically for file sharing, but having stopped, while it might work towards clemency, does not guarantee that you won't be liable should the record labels decide to press charges, or sue you in civil court. They would have stored your IP, the time and date, and the infringing item you are alleged to have been sharing at the time. The question of uploading is tricky. Since they press the issue as a copyright issue, the question is whether it's a "derivative work" - whether the bits and bytes that make up the data in question were "derived" from the source piece and not covered under the first amendment's protections in cases of parody, etc. Usually, the process is that they notify the ISP by sending a DMCA Cease and Desist order. The ISP then forwards you a copy of the complaint. At that point, you either ignore it and share some more (not good), stop sharing (good), or file a counterclaim (don't bother; it's a liability if you don't know what you're doing, and can cost you more than you can possibly imagine). NO SERIOUSLY READ THIS NEXT BIT AND CHILL OUT: The above is meant to be objective information to inform you of the worst case scenario. Don't let that make you feel too grim. The chances of getting nailed are slim and even if you do get a C&D, just keep off the torrent/sharing apps and you'll probably be fine (but don't acknowledge it directly, either). If you are truly paranoid, consider consulting an attorney and have them set your fears aside. Many offer free 30 minute chats for quick advice for things like this, and they're specialists in this area.

Short answer, an ISP is required by law to keep logs of every I.P. address on a customers activity for a minimum of 3 years. If someone is seriously looking for theft of media or files, all they need do is get a court order for your ISP to see where you have been. That being said, If they haven't come after you yet, they most likely won't. That is unless you were downloading and uploading tons of files.