>"If someone does something nefarious using my exit node (or the free wifi at my coffee shop) then that shouldn't be my responsibility.
Without even getting into the intricacies and ethics of pooling and providing Spartacus communal anonimty. Wouldn't lending tools that are used for a crime being an accessory, or an accomplice, or at least aiding and abetting?
It's even a bit ridiculous, "If someone does something nefarious with my gun, that's not my responsibility" Yes? Yes it is? Maybe that line is used for something more borderline, but that's definitely your responsibility, if you are allowed to do that at all it's only because of the difficulties of legal procedures and the pressumption of innocence, but that doesn't mean that it's ok to redistribute CSAM and leaked data.
It's murky AF, which is why I asked about precedent after stating [and justifying] my own opinion.
Intent has a lot to do with liability.
My intent with my hypothetical coffee shop is not to provide a dark corner for people to do illegal things online; it is instead my intent for smiling patrons to have a free slice of Internet to go with their not-free cup of coffee. It's just a service that I provide, along with a restroom and a place for people to gather. My options for monitoring it are limited, but if I do notice someone doing stuff that's NFG (whether on the internet or in person), then I'll turn off the taps and tell them to leave. They won't be my customer anymore.
That's not so dissimilar to my ISP's intent when they sell me a month of internet access at home. Their monitoring options are very similar: Observation is difficult (brought to you by NordVPN and https), but if they notice something that is definitely nefarious then I'm likely to be getting a sternly-written letter and/or disconnected.
Most people are generally good -- and most coffee shops (around me, anyway) have free wifi.
The precedent here is that it seems to work, and that we don't have a long and storied history of imprisoning owners of coffee shops and ISP networks.
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Now, if a person were to hang up a sign on the front their coffee shop that says "FREE WIFI! GET YOUR CSAM HERE!" then that's... that's a rather different kind of intent, and in a fair and just world it wouldn't be too long before the person who hung up that sign would behind bars.
Why is your responsibility for things you didn't do? Providing a road that a bad person drives on is not a crime.