They were placed under complete centralized control, with the Police Affairs Bureau (警保局 [ja], Keiho-kyoku) of the Home Ministry at their core.

[5] After the surrender of Japan, the Supreme Commander for the Allied Powers regarded this centralized police system as undemocratic.

Cities and large towns had their own municipal police services (自治体警察 [ja], jichitai keisatsu), and the National Rural Police (国家地方警察 [ja], Kokka Chihō Keisatsu) was responsible for smaller towns, villages and rural areas.

[6] However, most Japanese municipalities were too small to have an effectively large police force, so sometimes they were unable to deal with large-scale violence.

[7] As a response to these problems, complete restructuring created a more centralized system under the 1954 amended Police Law (警察法, Keisatsu-hō).

[3] Prefectural Public Safety Commissions (都道府県公安委員会 [ja], todōfuken kōan īnkai) are administrative committees established under the jurisdiction of prefectural governors to provide citizen oversight for police activities.

In the Tokyo Metropolitan Police Department, the name of Superintendent General (警視総監 [ja], Keishi-sōkan) is used.

Designation and dismissal of these high-ranking officers are delegated to the National Public Safety Commission.

In addition to the administration of the police radio networks, they provide inter-regional patrol units and air support: automobile patrols (自動車警ら隊 [ja], jidōsha-keira-tai) and a police aviation unit (警察航空隊 [ja], keisatsu-kōku-tai), and many other assets.

[14] In the Empire of Japan, the criminal investigation was presided over by prosecutors, like the ministère public does in French law.

[15] They are mandated for critical incidents except for terrorism,[16] but in some rural but well-versed prefectural police like Aomori Prefectural Police, these detectives can form a counterterrorism task force together with uniformed officers and riot specialists.

On the other hand, the Tokyo Metropolitan Police Department Superintendent General represents not only the highest rank in the system but also assignment as head of the TMPD.

[23] In the pre-war period, police officers wore jackets with a stand-up collar.

In 1946, the jacket was changed to four-buttons, open-collar style with vent and in 1950, a new police duty belt to wear gun and baton was adopted.

[26] Through the campaign against the Treaty of Mutual Cooperation and Security Between the United States and Japan at the end of the 1960s, helmets and protective gear for riot police officers were improved.

Finally, imports from the United States were resumed, with S&W M37 and M360 revolvers having been purchased for uniformed officers.

[31][better source needed] And some elite detectives, bodyguards, or counter-terrorism units such as the Special Assault Team being equipped with 9×19mm Parabellum calibre semi-automatic pistols such as the Heckler & Koch USP.

Tactical units of crime branches (Special Investigation Team of the TMPD, for example) also introduced a semi-automatic pistol-caliber carbine variant of MP5K (unofficially called the MP5SFK).

[33] In Japan, there are about 40,000 police vehicles nationwide with the most common patrol cruisers being Toyota Crowns, Subaru Legacys and similar large sedans, although small compact and micro "keI" cars are used by rural police boxes and in city centers where they are much more maneuverable.

Pursuit vehicles depend on prefectures with the Honda NSX, Subaru Impreza, Subaru Legacy, Mitsubishi Lancer, Nissan Skyline, Mazda RX-7, and Nissan Fairlady Z are all used in various prefectures for highway patrols and pursuit uses.