Introduction

On 27 November 1998, a short letter was published in the Guardian newspaper in London. It read:

The letter was published two days after the landmark first decision of the Judicial Committee of the House of Lords, ruling that Senator Pinochet was not entitled to claim immunity from the jurisdiction of the English courts in respect of a Spanish extradition request to face criminal charges for torture and other crimes against humanity, while he was head of state in Chile. The Guardian letter and the Pinochet judgment were based on a theoretically simple – but politically explosive – premise: no rule of international law existed to prevent the arrest in London (whether for the purposes of prosecution before the English courts or for extradition to a third state) of an American or Chilean national for acts occurring outside the UK and involving no real connection with the territory or nationals of the UK.

The Pinochet judgment was a landmark because it emphasised the role of national courts – Spanish and English – for the prosecution of the most serious international crimes. It relied on three principles:

1. that there are certain crimes that are so serious that they are treated by the international community as being international crimes over which any state may, in principle, claim jurisdiction;

2. […]