What are the major differences between Security Forces (3P0X1), Military Police (31B), USMC Military Police 5811, and Master-at-Arms (MA)?

I’ve worked with Army Military Police and from what I understand they focus more on Infantry related concepts such as convoys and off-base patrols when deployed. Security Forces rarely do Infantry work, and they are more focused on base security and law enforcement. Although this is from a National Guard perspective and I’m sure active duty does a lot of law enforcement work on the Army side.

Security Forces core duties: Base patrol and law enforcement, flight line security, and gate entry control. Active shooter response is a big focus now as well.

Most Army MPs do more time in the Field than Law Enforcement but all get training for and do law enforcement missions. when you graduate from Army MP AIT now you have completed all the training to be a certified officer in Missouri (where the training is).
Good Luck to your friend.

For the Navy, CNIC doesn’t care about LE. The Navy only cares about ships in the sea and planes in the air. The current focus for the LE aspect is ATFP. The LE side is very under trained and outdated. However where the rage differentiates from other branches LE jobs is the CRG/ CRS side of things. Expeditionary is a whole different animal.

I had Military Police experience on the Army secondary MOS 95B. When I submitted my conc=version packet it was a plus for me. Master at arms are now more in line with Army MP's and AF Security Police, MA's perform not only UCMJ enforcement they alo now do a lot of force protection, and security work. As an MA I was responsible for Good Order and Discipline aboard ship. On shore duty it was more involved with not only Good Order and Discipline, but also patrolling, and more UCMJ enforcement.

I served as a NAVY MA and now AF Security forces. Biggest difference is that when in a security force function MA's end up getting mixed un with the rates. So you can serve alongside a Boatswains Mate who now thinks he is a special forces operator because het got into a security unit. It ruins it. AF does not mix other MOS's into their security forces and it shows. AF SF is much better. In addition AF provides basic infantry skills right out of tech school - Navy doesn't. Navy makes you a stick cop and whatever command you end up depends if you get additional training. Some guys went expeditionary and got good training. Some guys became gate guards at ab ECP and thats it. AF saturates their SF with training from the start. I think they have a better program. However I did get my hands on a lot in the Navy that I might now have had the same opportunity to do in the AF. The Navy deployments are more complex and better as a reservist. But I know of Af SF units that routinely deploy to Afghanistan as front line guys. Its a give and take. I loved my time as a Navy MA but glad IM not there anymore. I would absolutely pay a visit to MA A school Lackland if I go down there.

The person who you are helping should talk to all branches of service and find out as much information as possible on each one and make a determination

Having been both Army Military Policeman and USAF Security Police I think I can answer a couple of questions. The Army's M.P.s are policemen who enforce the UCMJ and other directives as published by higher headquarters or local directive. OK I simplified. Your duties can be wide and varied depending on the nature of your unit's assignments. For example, I was assigned to the U.N. Joint Security Force, Panmunjom, Korea, directly from training at Fort Gordon, GA. I completed a dream sheet shortly before my time was up in Korea. I requested Vietnam as my next duty post. I received my orders for the 560th MP company Vietnam. During that tour, as an NCO, I did convoy escort, apprehended military members for narcotics, armed robbery, homicide, conduct unbecoming and other infractions. I was the driver/bodyguard for the senior advisor of II Corp. I function as the first responder for our II Corp CID. Nearing completion of my time, I completed another dream sheet requesting duty on the west coast. I was assigned to the 4th MP company, 4th Inf Div at Fort Lewis, for the duration of my three year enlistment. Following my discharge I went into civilian law enforcement. My military experience was a help. Civilian law enforcement is quite different from the military and needs to be understood. I can say with all sincerity that my time in the Army provided me with experiences enough for six lifetimes.

The major difference depends on the branch of service you are in; then the kind of work you are assigned to do. A Master at Arms aboard a ship will not do what a Master at Arms on a shore duty station does. The USA and USAF do a lot more kind of law enforcement than a master at Arms do in my book. (I was one of the first 400+ sailor selected for the MA rate) we went to the air force police school in texas, we got training from them and we also got training by the navy on what we would be doing onboard ship and what we could expect from the navy's side. The training on base patrols and things that pertained to the land base law enforcement which we could use on the navy base when the navy got their act together on what the MA rate was supposed to do. The big thing you have to look at is what, how and why each service does what it does when it comes to the job of law enforcement. (I have been out of the MA rating now for 44 years and a lot has changed since them (we didn't have a Ma Duce machine gun mounted on the side of the ship when we came in port as they do now today.

Now days your local LEA’s don’t want Military Police experience too much PTSD exposed veterans. SCSP I know for a fact will not hire a veteran with law enforcement backgrounds.

Honestly it does vary based on Major Command, Assets, Mission, etc. Security Forces has a security side and a law enforcement side. Then you can add an additional specialty (depending on component) such as K9 handlers, Combat Arms (weapons guys/gals), Electronic Security.

In the ANG, for stateside most of our missions do focus on the security aspect. I can't think of many Guard units that solely handle their own law enforcement (LE) because of jurisdiction agreements with local LE. I want to say there is concurrent, proprietary and exclusive jurisdiction. We worked with the local civilian LE agencies who could patrol/respond/arrest suspects on our installation. At Buckley, we are a tenant unit so our active duty counterparts actually run the law enforcement side, so I can't speak on how they fully operate.

However, just because a unit doesn't have an LE mission doesn't mean that they do not conduct LE training. The Security Forces Center outlines what training requirements need to be met annual by all Security Forces members/units At a bare minimum: challenging, handcuffing and searching, combatives, high risk vehicle stops are being taught, weapons qualifications, shoot-move-communicate.

OCONUS we focus on Total Force. Depending on what expeditionary location you deploy to, you can go to a base that Security Forces does both LE and Security or focus' on one over the other.