From Dragon Eye Atlas
Their purpose is to keep the roads of the empire safe and clear for all travellers. In this, they have been so successful that their role, which was originally limited to the High Road itself, has now expanded to all roads within the empire, though only the High Road is patrolled daily.
On the roads, the Road Wardens have full police authority and can question or arrest any traveller who is not a noble. Even for nobility, a Road Warden has the right to inquire about his origin and destination of travel and to be answered truthfully.
Road Wardens are also to be allowed entrance into any settlement or fortified roadside inn at all times of day and night.
Aside from their official authority, the good reputation of the Road Wardens makes them trusted authorities in many remote parts of the realm, and many villages or waystations turn to a Road Warden for justice when a local dispute needs to be moderated. There have been talks within the court at Aenenus on granting Road Wardens limited judicial authority for such cases, but nothing has come of it yet.
In addition to securing the roads, a large part of the day-to-day job of a Road Warden is checking the roads he patrols for damage, fallen trees, mudslides and any other obstructions or problems and reporting them to the nearest town or city so they can be taken care of.
The Road Wardens are a light cavalry force, equipped with horses, swords and light armour. Though they are neither trained nor equipped for war, many of their garrisons store heavier weapons and armours in case some especially nasty bandit camp needs to be smoked out.
Most Road Wardens are also trained and equipped for spending a few days in the wilderness. While they usually stay in roadside inns, towns or garrisons (where present), it can always happen that the next such location cannot be reached before nightfall.
On the Imperial High Road, the Road Wardens typically patrol in groups of four, sometimes splitting up into two pairs if needed. On the smaller roads of the empire, the group size of a patrol drops to three or two, and especially in more distant or remote locations, lone wardens are not an uncommon sight.