The House of Lords has ruled that the Chilean government will be able to make representations to next week's hearing to decide if General Augusto Pinochet is immune from prosecution for human rights abuses.

The decision was made on Wednesday, after written representation from the Chilean government. Stating that it did not wish to provide a "personal shield" for the former dictator, the government went on to argue that in the interests of Chile's national sovereignty, any investigation and trial of Pinochet should take place only in the country's own courts.

Lord Browne-Wilkinson, chairman of the panel of three Law Lords hearing the representation, ruled that it would be wrong to exclude the Chilean government and that it should be able to make both written and oral representations at the new hearing, which begins on Monday. He also ruled that, given the lateness of its application, the government should serve an account of its case on all other parties to the hearing by no later than 20.00 hours, GMT, on Thursday.

Alun Jones QC, acting for the Spanish government which is seeking Pinochet's extradition for trial on charges of torture, hostage-taking and conspiracy to murder, had earlier objected to the Chilean government's application. Its late arrival, and uncertainty over the issues it would raise, aroused fears that "it will lead to not only a longer hearing, but a more difficult one, which could have been avoided by putting in heads of argument long ago," he argued.

The Law Lords had ruled in November that the general had no immunity from arrest and extradition to Spain. That ruling was overturned following allegations of possible bias by Lord Hoffmann, who had failed to declare his links with the human rights organisation Amnesty International.

As the country's highest court, the legal challenge against the House of Lords ruling--especially on the grounds of possible bias--is unprecedented. Consequently, the British legal system has entered uncharted territory under conditions in which it is dealing with an already highly contentious and internationally high profile case.

In an effort to restore its credibility, seven judges, instead of five, will hear the arguments next week. The Law Lords also agreed that a group headed by Amnesty International would be able to make representations, although it restricted the Human Rights Watch organisation to making written submissions.

Nonetheless, the Lords efforts at impartiality are being severely strained. The charge of bias saw Pinochet's lawyers objecting to the inclusion of Lord Woolf in next week's panel, after they learned of his invitation to host an Amnesty International fundraiser. Woolf's decision not to participate in that event--because of his possible role in the forthcoming hearing--prevented the challenge against him, but he has now declined to sit.

Lord Browne-Wilkinson, the senior Law Lord who earlier declared his governorship of the British Institute of Human Rights, is included in the seven-judge line-up. But he is one of the four judges who overturned the earlier ruling by the panel that included Lord Hoffmann. The panel will also include Lord Millett, a high ranking freemason; Lord Hutton, the former Lord Chief Justice of Northern Ireland where Britain has been condemned for human rights abuses; and Lord Phillips, who presided over the Maxwell fraud trial that resulted in a whitewash.