Traffic police

Traffic police or traffic officers, often referred to colloquially as traffic cops or traffic enforcers, are police officers who direct traffic or serve in a traffic or roads policing unit enforcing rules of the road. Traffic police include officers who patrol major roads and also police who address traffic infractions on other roads. It has been noted that:

...traffic police, who are regarded as peripheral to most police forces, participate in both authoritative intervention and symbolic justice. Perhaps alone of all the assignments, traffic police are full-service police. They are different from the rest, however, because their work is limited to a particular venue — namely, public thoroughfares — and to particular people — namely, those who operate motor vehicles. But in terms of work, traffic police are detectives as well as patrol officers.