We posed this same question to a Highway Patrolman last year before we bought our first TT. First on the legality of people and pets riding in the TT and secondly on the safety. In Montana, no people are allowed in a TT, but they can ride in a 5er. Pets are legal in either case. As for the safety, he said he has seen too many accidents involving towed vehicles with seriously injured or dead animals to ever consider it for people or pets to be in any rig. It was enough for me. My dogs ride in crates in the open bed of the truck. They fare just fine.