The good faith assumption that the other party is trustworthy (within reason) does not exist on the street. This is why driving is regulated, and most places in

The good faith assumption that the other party is trustworthy (within reason) does not exist on the street. This is why driving is regulated, and most places in the world demand driving licenses, the car to be insured and the owner to be ultimately liable for the car. Chainsaws are rarely regulated, not registered and the even of serial murderers using it is considered rare. Do note however, that some legislations might have the owner on the hook for negligence if they didn't exert reasonable efforts to hide away dangerous machines and substances.