Which branch has the best military police?

Let me splain something to you. For every combat soldier there are about 20 in the rear forces that support them so that they can get their job done. Every mother's son and daughter has a role in our defense system. Some are duty soldiers some are mac daddy trained to offset all those half-steppers. Every in the military contributes even if he holds the punch at the Chaplains office to get a tough shit card punched. I have spoken.

Well Air Force have different types of security forces.The SP on the flightline guarding aircraft. The SP on base, working the gates or doing patrol
On base. The SPs that work at the missile silos across the country. Those are the best trained besides Combat Control in the USAF.

As a former Army MP, I would definitely say that the Army MPs preform a lot more missions than either the Air Force or Marines. I served 10 years in the Army and did two tours in Iraq and one in Afghanistan. In Iraq we were always on patrol and stayed outside the wire. We also trained a lot of the Iraq army and civilian law enforcement. There wasn't any role or mission we didn't or couldn't do.

From personal experience at Bagram 2010, the Air Force SF their really got their rocks off harassing the WarFighters. I don't know if it was that particular unit, or the SF in general, but they went out of their way to try and eff with the Army stationed there. Impounding vehicles for seatbelt infractions. When wearing full battle gear, you can't fit a seatbelt in a civilian hodgie van around all that. They sat and waited for guys coming off of aircraft being picked up by the ALOC staff.

Biased here, but in the Army I have served as a patrolman, combat MP, physical security, on loan to DEA via drug suppression team and as a investigator. I loved every second of it all.

Army. Is there any other Branch. ;-)

Had the unique opportunity at our Reserve Training Institute to put together an SOP for our 31B instructors to teach Air Force Reserve Security , U.S Army MP tasks for a QRF during a Army National Guard Brigades deployment.They were very receptive to the training and it helped them prepare for their mission.Each branch of service should cross train with their best practices.One Team Taking it to the Enemy

I dont think there is a "best". We all have our own jobs to do, some with more emphasis on LE or force protection. Im a MA myself and my command is 98% LE, responding to all sorts of different calls for service.

I mean what would the competition consist of? Writing tickets and seeing who can say "I'm pretty much infantry" with a straight face??? :) just kidding... kind of...

Army first, Navy last. Lived in army housing for three years in Hawaii, the AMR or Crater as we called it and they always treated us with respect and professionalism. They used a common sense approach to enforcing regulations. The navy on the other hand uses a slightly different approach. Lets treat everyone like ass holes, Lets try to find a stupid obscure regulation and enforce it with great tenacity. Lets try to make life a miserable as possible for our fellow sailors. Now I will give the Navy some credit. I retired about 15 years ago and just before I got out they made the MAA a rate (MOS) that you enlist into from day one and their training program at Lackland AFB was revamped. Now the DOD cops on the navy bases are a joke. They are mostly way over weight and lazy.