That's basically how things used to work in Germany. It used to be that if someone torrented movies on your internet connection, you were fined. No ifs, no buts, they monitored 100% of the public torrents and courts agreed with 100% of the fines. And they didn't care who did it - if they didn't know (which is almost always true) they fined the owner of the internet connection. It was a really really bad law. For 10-15 years after every other country had public wifi hotspots, Germany didn't because the owner would get fined for every torrent. After a very long time, they eventually passed a law saying public wifi operators didn't have to pay.