A gendarmerie or gendarmery is a military or paramilitary force charged with police duties among civilian populations. Members of such a force are typically called "gendarmes". The Shorter Oxford English Dictionary describes a gendarme as "a soldier who is employed on police duties" and a "gendarmery, -erie" as "gendarmes as a body". The term maréchaussée (or marshalcy) may also be used (e.g., Royal Marechaussee) but is now uncommon.
Here is fine ass example of the type of boats they use: