Brazil
In Brazil, traffic policing is the responsibility of state and federal police forces accordingly to the highway administration status. State administered highways (usually shorter, within state borders, two-way, single lane, lower traffic) are policed by a branch of the Military Police forces, called State Highway Military Police. At the same time Federal highways and roads (longer, crossing state borders, some double lane and high-traffic) are the responsibility of the Federal Highway Police.
Read more about this topic: Highway Patrol