Ironies abound in the British decision to let former Chilean strongman Augusto Pinochet go home for "compassionate" reasons. Compassion, of course, was notably scarce under Mr. Pinochet's iron-fisted rule. It is tempting to argue that the general deserves nothing less than the justice he meted out to the thousands who were killed, tortured or "disappeared" during the 17 years he was Chile's supreme leader. That would be wrong: Denying him justice only compounds the sins that were committed, it does not rectify them. Let Mr. Pinochet go home. Chile should deal with its past. More importantly, a powerful legal precedent has been established: Dictators can no longer hide behind the fiction of sovereign immunity to shield them from their crimes.

Mr. Pinochet's legal drama began in October 1998, when he went to Britain for treatment of a back ailment. Traveling as a senator for life, who had been awarded legal immunity by an act of Parliament before he relinquished power, he must have felt invulnerable. Yet Spanish Judge Baltasar Garzon was not cowed. He issued a warrant for Mr. Pinochet's arrest and extradition to face trial on 35 counts of torture and conspiracy to torture. Although the alleged human-rights abuses were committed in Chile, Spain, along with other European nations, believes it has the legal right to try the general for crimes perpetrated against its citizens.

Mr. Pinochet claimed that, as a former head of state, he was immune from prosecution for those acts and could not be extradited. In two separate stunning decisions -- the first was overturned after allegations of bias against one of the judges -- Britain's Law Lords disagreed, holding that international treaties override the principle of sovereign immunity.