However, they are hampered by the fact there is no international register of people who have been deported from other countries. However, the decision by the Metropolitan Police not to refer the case of Mr Kalejs to the Crown Prosecution Service highlights the basic weakness of Britain's war crimes legislation. Prosecutions difficult No war crimes legislation was enacted in the UK after the post-war Nuremberg trials because politicians and civil servants said no war criminals had entered the country. The government only passed the relevant act in 1991 after mounting evidence and pressure from campaigners. But in the case of alleged incidents that took place during the 1939-45 war, the War Crimes Act makes it hard to bring a prosecution.
Credible evidence is often difficult to find.
Crucially, witnesses have to be able to identify clearly and uncontroversially the defendant and there must be proof that defendants were in command and not simply following orders. Last year it emerged that Anton Husak, who was on a list of suspected war criminals supplied to the government by the Soviet Union in 1988, would not face charges. But the CPS said there was insufficient evidence to prosecute. Since the 1991 Act came into force a special police unit of the Metropolitan Police has investigated 376 cases. But in nearly a third of the cases, the suspects were already dead.