Ah TheCurmudgeon,

SWC has passed through this area of interest before.

Just using 'gendarmerie' in a simple search I found threads:

1943 - Reorganization of the Imperial Iranian Gendarmerie (x7 posts 3k views)
What are the SWC thoughts on policing in combat? (x37 posts 11k views)
Federal Restrictions on using U.S. MPs for law enforcement on foreign soil (x40 views 7k views)
Law Enforcement Advisory Capability as a Major Shortcoming (x32 posts, 5k)
Cops Show Marines How To Take On Taliban (x20 posts, 5k views)
U.S. Police in Peace and Stability Operations (x6 posts, 4k views)

Incidentally during 'The Troubles' the British Army increased the size of it's military police, with two regiments deployed at one time - when the army had responsibility for LE long ago.

In the Balkan peacekeeping much emphasis has been on the presence of small, company sized gendarmerie units; invariably from France, Italy and Spain.

In Afghanistan the UK was handicapped in deploying police advisers as most LE have no arms training, let alone experience; hence the reliance on our few armed police bodies (RUC/PSNI and MoD Police).

Didn't the USMC or US Army announce last year standing up a new enhanced military police unit?