A police officer that pulls you over, that ask you to sit in the front seat of his car, is doing it for a reason. He's employing a tactic to basically determine whether there are indicators that would lead him to search your car. Interdiction cops do this very frequently. Usually it's the highway patrol and they're always after information. His whole goal is to engage in conversation with you. So, don't fall for that. If he asks you to sit in the front seat of his car, you don't have to sit in the front seat of his car if you don't want to. He can make you get out of your car, he can make you stand on the side of the road, but in my opinion, he can't make you sit in the front seat of his car unless you want to.