The following fact seems clearly established now: the British occupation army in Basra arrested people and tortured them; and in some cases (e.g. the hotel receptionist, Baha Mousa) tortured them to death.
There are three types of people who are culpable.
First, among the lower ranks of the British army there are sadistic torturers who enjoy the protection of their peers and probably their superiors. Every legal measure must be deployed to find, prosecute and imprison these people for life.
Second, the officers in charge of those units whose soldiers engaged in torture should at the very least be expelled from the army. If it can be established that they colluded in the torture (i.e. by knowing it was happening and doing nothing to prevent it), they too should face imprisonment.
Third, the same test - applied to British army offices - should be applied to the Prime Minister at the time (Tony Blair) and his defence minister (Geoff Hoon). If any government minister knew that torture was taking place and failed to take steps to stop it, they also should face imprisonment.
It’s just possible that a private soldier may be thrown to the wall, but the army top brass and government ministers will almost certainly walk away unscathed. Such is the rotten state of the country we live in.