Military Police Brigade

The Military Police is the most prestigous due to their work allowing them to live within the Inner Wall. However, it is also the most corrupt due a lack of oversight compared to the other sectors of the military. Only the top ten alumni from trainee squads can apply for the Military Police.

Duty
The Military Police is the police force within human territory. Not only do they maintain order, they serve as the king's guard. Since they do not normally come in contact with Titans, they must have special permission to use 3D gear and usually carry firearms instead. They are also in charge of tax collection and land distribution as seen in Ch. 15 when a couple policemen monitor farm production.

Qualities
The Military Police is supposed to be an elite unit made of the most skilled soldiers due to its rigorous standards. The reality though, is a lazy, corrupt system that benefits from the powers granted to it.

The senior officers spend all their time gambling and drinking while leaving recruits to do all the work. They also pilfer taxes and misappropriate land as a recruit, Marlo, mentions in Ch. 31. This corruption is well-known with many people criticizing their lack of care for anyone other than themselves. 

However, many trainees still dream of joining the Military Police because it will allow them to live within Wall Sina and safety. Also, being so close to the center of human territory, most policemen have relatively little experience fighting Titans as compared to the Scouting Legion or the Stationary Guard.