Without knowing self-defense or a form of Martial-Arts, Law Enforcement would have no meaning, other than just using armed weapons, when dealing with criminals from long range distance. Since most Law Enforcement officers have to have the need to learn basic self-defense, to Pressure Point Counter Tactics, such as Aikido, Hapkido, Jiu-Jitsu, and other grappling related moves, but in some cases, if necessary, using the hands or feet in life and threatening situations.
Though police officers may have a bad reputation to go over the distance about police brutality and abusing their power in Law Enforcement, Martial-Arts is only interpreted in the hand of the beholder, and what must be used to pin down a criminal or a dangerous suspect of a crime.
This topic is not so much what art is best suited in Law Enforcement, especially in the United States, but how and what arts could be used in a dangerous self-defense position, as in other countries, having different laws, what works for one nation, may not work for the other, since no one likes to feel or become a victim by police brutality.
Many may fear of police officers, or those who are in security and Law Enforcement positions, but the point of a Martial-Art is plan and basically simple, it was meant to defend ones own life, and to protect the innocent or an individual to not become a victim of a crime.
Through out the country in the United States, various of styles is implemented in Law Enforcement, where experts in various of Martial-Arts are taught in Police Academies more than ever.
As it is now required for a Law Enforcement personnel, to ever more increase their security and self defense skills, which also means keeping in shape. Though Law Enforcement is more about protecting the public, Martial-Arts is a discipline or military form of constructing an individual, to become a weapon, as the use of Martial-Arts, is a form of a weapon without arms and protecting oneself without weapons, where armed weapons can turn an individual to become a weapon of Self-Defense.
Whether the art maybe Japanese Martial-Arts such as grappling and weapon disarmament, Korean Martial Arts in Hapkido, or a mixture of American and Chinese influence such as Kenpo/Kung-Fu, to Military Self Defense from Israel Krav Maga, even Reality Based Martial-Arts, without a form of Self-Defense, Law Enforcement would have no meaning to protect and serve the community.
Martial-Arts is more than just striking and defending, it changes an individual to find their inner strengths, and interpret the world what they see with their own eyes, when speaking of Self-Defense.