“We are seeing a continuous pattern of serious allegations of mistreatment, ranging from kidnapping to torture,” Ms. Craig said. “The government is not saying ‘This did not happen’ or ‘We will make our case for why it did.’ It has simply been trying to close the door of the courts. This was nothing less than a patent attempt to immunize itself by hiding behind the Americans. But the court said no.”

The judge’s ruling also affects three Iraqi men with similar cases who can now also sue for damages, pending the appeal, lawyers said.

And three weeks ago, a British appeals court allowed a Libyan politician, Abdel Hakim Belhaj, and his wife, Fatima Bouchar, to bring a case against the British secret service, MI6, and the former British foreign secretary Jack Straw. Their suit accuses MI6 of complicity with the Central Intelligence Agency in their detention, deportation and subsequent torture in their home country a decade ago.

“There is a compelling public interest in the investigation by the English courts of these very grave allegations,” the court ruling said.

Government lawyers indicated that they would appeal the Rahmatullah and the Belhaj rulings.

Few believe that the British cases will lead to any significant change in the United States, where the Obama administration has been reluctant to investigate, let alone prosecute, allegations of torture under the Bush administration. American courts have consistently thrown out lawsuits against American officials. And most recently, the Obama administration refused to declassify information needed for the Senate Intelligence Committee to publish its report on C.I.A. torture.

“This British case shows that despite Obama’s intense efforts to keep the lid on disclosures about Bush’s torture, people committed to ending this terrible precedent of impunity for torture keep pushing the lid ajar,” said Ken Roth, executive director of Human Rights Watch and a former federal prosecutor.

Mr. Roth said that the British cases might “shine a spotlight on some of this torture,” but were unlikely to make similar lawsuits easier to mount in the United States. “Several such cases have been tried, but they all have been dismissed at the government’s urging on grounds of state secrets or immunity,” he said.