This video shows part of SAT's training.
In 1977, Japan was threatened with the hijack in Dhaka. The Red Army hijacked one Japanese airplane, demanded to set their members free and a ransom of 6 million dollars. The Japanese Administration took measures beyond the law, released them and pay the ransom. This enables the Red Army to spread all over the world and many countries criticized the Japanese action.
This affair taught Japan a lesson. Japan determined to build an anti-terrorist team in the police; This team is to be called SAT (Special Assault Team). It is said that members of SAT were lectured by GSG9 and SAS.
Once being a member of SAT, his name is deleted from the list of the police. One reason is to protect him against terrors. Another is a Japanese peculiar reason: to prevent him from being charged with murder when he shoots and kills terrorists; once upon a time, a police sniper who had shot and killed a seajacker was specified by a leftist lawyer and was actually charged with murder.
from http://www.britishtroops.co.uk