"In Ancient Greece, publicly-owned slaves were used by magistrates as police. In Athens, a group of 300 Scythian slaves was used to guard public meetings to keep order and for crowd control, and also assisted with dealing with criminals, handling prisoners, and making arrests. Other duties associated with modern policing, such as investigating crimes, were left to the citizens themselves.[10]
Before its decline, the Roman Empire had a relatively effective law enforcement system. When under the reign of Augustus the capital had grown to almost one million inhabitants, he created 14 wards, which were protected by seven squads of 1,000 men called "Vigiles," who guarded against fires and served as nightwatchmen.
If necessary, they might have called the Praetorian Guard for assistance. Beginning in the 5th century, policing became a function of clan chiefs and heads of state" (ez is wiki, az angol)
Házi feladat: a magyar rendfenntartó szervek története.