You're not very bright are you?
....
Stop assuming you have a clue, because clearly IT is not your department.
Good thing I did this whole introduction about how I came here to learn, and I was just starting off. Clearly IT is not my department, if my information was incorrect please point it out.
In regards to
1. If he's running a TOR node meaning: he's allowing others to use his computer as a jump point, they could be using that connection to download and upload TOR (This is discouraged but not at all improbable)
2. If his wireless access point has been hacked and used to download TOR files then his ISP would obviously assume he was the culprit...
3. If his system has been trojaned/rooted then just as with tor it could be used as a pivot point for downing/upping torrent files.
4. If he was running a firewall he'd be able to tell what ports are open on his system.
1) Yes this is possible, but if I remember correctly these would be the precautions you take (
https://www.torproject.org/eff/tor-legal-faq.html.en), and this still doesn't take away from the fact you assume, and accept the risks of that scenario no matter how unfair it seems.
2-3)If his wireless is hacked, you could keep track of the usage of it, and quickly determine it. This doesn't not take away the risk of getting called out by your ISP. People have had their lives ruined by hackers downloading CP through their computers, whether they were guilty or not..(now this is extreme I know) they were still responsible. If his system has been compromised, well unfortunately that does suck. There should be some indications of this intrusion, and actions taken appropriately.
4) This pretty much doesn't change what I said about the firewall keeping prying eyes from seeing his traffic....his ISP still saw or was notified of behaviors on his IP. Seeing what ports are open doesn't nothing to change that fact. And is quite irrelavent unless the former points were the cause. Then actions would need to be taken.
If any of my information is incorrect, please correct it (addressed to everybody), as yes I am new, but I am not dumb. I have torrented for years without so much as a notice, if you get hit with a notice it is still your responsibility to comply. Pirating is risky business, but this risk can be mitigated with proper precautions.