I'd avoid hosting a tor exit node at all costs, considering that they are a lot of bad actors on tor. Even some 3 letter agents can host cp on your tor sites and then accuse you.
>Even some 3 letter agents can host cp on your tor sites and then accuse you.
You can't use exit nodes to run "tor sites", because they only allow outbound connections. You can run hidden services, but they work entirely through relays (ie. not exit nodes). Given that hidden services are end to end encrypted (none of the relays in the middle can see the traffic), and to my knowledge relay operators have generally not been prosecuted, your specific scenario is unlikely to play out.
That said, if you're running a exit node and the FBI wants to frame you, they can still use your relay to conduct some illegal action (eg. uploading CSAM to some clearnet site), and pin it on you.
If you become an ISP (with your AS) then it is less of a concern (in the US) since ISP have some protections. Emerald Onion [0] is an example of doing this. Actually in their faq [1], they state:
"Digital Millennium Copyright Act Safe Harbor
The Digital Millennium Copyright Act (DMCA) offers four safe harbors to protect ISPs from copyright liability for the acts of their users, provided that certain requirements are met (17 U.S.C. § 512). Emerald Onion is a section 512(a) “conduit” provider."
If you want to read the section it is here: https://www.law.cornell.edu/uscode/text/17/512 (it is generally about "Limitations on liability relating to material online" not just copyright)
