What pistol is issued for military police?

The Colt 1911 Model .45ACP was the standard issue service pistol in earlier years, and is still issued even today. It is one of the most reliable pistols ever made and is still a very popular gun. But in recent years the standard issue side arm of the military has been the Beretta M9, which is a 9mm semi automatic service pistol. There is also a new service pistol that the military has started to use, which is the Smith and Wesson M&P semi automatic service pistol. The M&P stands for Military and Police. It is most commonly chambered in 9mm and .40cal for the military and police but there is also a .357 version available.
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Currently Military Investigative Agencies like Air Force Office of Special Investigations, Navy Criminal Investigative Service, and Army Criminal Investigations Division carry Sig Sauer P226 (also known as the M11), chambered in 9mm.
There is ongoing discussion and testing of new and larger caliber weapons, however none has made it to front line units like mine. The main problem with issuing a weapon chambered in a larger caliber than 9mm is the U.S. Military's involvement in the North Atlantic Treaty Organization (NATO) which requires Military units operating under its purview (which the U.S. does) to only use pistols chambered in 9mm. Until an agreement is made or a policy changed I do not see the U.S. Military using 9mm pistols in a deployed environment.
The U.S. Coast Guard (USCG) is exempt from these requirements, because of its maritime law enforcement mission, and has switched to the Sig Sauer P229 chambered in 40 caliber, this occurred in 2006. However, USCG units who are deployed in support of NATO operations (Operation Iraqi Freedom and Enduring Freedom) are required to use the Beretta M9.
It should also be noted the 9mm round the U.S. Military uses is required to be a full metal jacket (FMJ), not a hollow point. Which, as any ballistics expert will tell you, goes through bodies and other material, instead of stopping in them.
In police work, however, one needs the ballistic projectile to expand and stop (preferably inside the suspect) releasing its kinetic energy. When bullets go through people, other people are put at risk.
Again, the USCG is exempt from using FMJ rounds during law enforcement mission, only while supporting NATO operations. The USCG now uses a hollow point round.