The brassard is often the most distinctive dress item of a Military Policeman on duty.
Usually worn on the upper arm, the origin of the brassard is supposedly to have been linked to military units used as police during the Indian Mutiny. It was during the Mutiny that certain units tied red cloth around their upper right arms in order to distinguish themselves from the mutineers.
In general, countries that drive on the left hand side of the road wear the brassard on the right arm, whilst those that use the right hand side of the road use the left arm. For example, the Royal Military Police wear the brassard on the right arm, and the US Army Military Police Corps use the left arm.