When can foreigners sue in US courts?

If cases at the US Supreme Court were named like pulp mystery novels, the appeal set for oral argument Tuesday might aptly be called "The Case of the Inscrutable Statute."

At the center of Sosa v. Alvarez-Machain is whether one of the nation's oldest laws, adopted by the first Congress, authorizes foreign individuals anywhere in the world to sue in US courts for money damages for alleged violations of international law.

What makes the case particularly difficult for the justices to resolve is the fact that virtually no information exists explaining why Congress passed the so-called Alien Tort Statute of 1789. There are no legislative findings explaining the problems lawmakers were seeking to address. The only direct evidence the court has to work with, according to legal scholars, is the wording of the statute itself. But those words have spawned competing theories about the law's meaning and scope.

The case is being closely watched as a potential landmark because it could determine the proper role of American judges in enforcing international human rights. It may also help define the place of international law in US courts.

Human rights advocates say the law, also referred to as the Alien Tort Claims Act, has helped create a forum for those least able to defend themselves against human rights abuses overseas.

"The Alien Tort Claims Act has been a beacon to the world," says Paul Hoffman in his brief to the court urging that it uphold existing legal precedents dating to 1980 that facilitate individual suits.

Critics say such a reading of the Alien Tort Statute raises significant constitutional concerns and could undermine US antiterrorism efforts. In addition, they say, it is putting American business at a competitive disadvantage in foreign markets.

The case before the court involves a lawsuit filed by a Mexican doctor abducted and brought to the US in 1990 at the behest of the Drug Enforcement Administration. The doctor, Humberto Alvarez-Machain, was allegedly involved in the torture death of a DEA agent investigating a drug cartel in Mexico. Rather than seek official extradition, DEA officials arranged for a group of Mexicans to apprehend the doctor and fly him to the US so he could stand trial on murder charges.

The charges against Dr. Alvarez-Machain were thrown out at trial. The judge said the government's case was based on speculation rather than evidence.

After returning to Mexico, the doctor filed suit under the Alien Tort Statute, claiming his abduction by Mexicans acting at the direction of the DEA violated international human rights. He was awarded $25,000. The award was upheld by the Ninth US Circuit Court of Appeals.

At the center of the appeal to the Supreme Court is a dispute over the scope of the law. The Alien Tort Statute clearly empowers federal judges to hear lawsuits brought by foreign individuals who were personally harmed by violations of international law or US treaties. But what is less clear is whether Congress sought to place any limits on which violations are applicable.

Lawyers for José Sosa, one of the Mexicans who helped in the Alvarez-Machain abduction, argue that the law merely establishes jurisdiction to hear such cases, but that Congress has never authorized this type of suit. Without additional congressional action, says Carter Phillips in his brief on behalf of Mr. Sosa, such lawsuits violate the constitutionally mandated separation of powers. "They have opened US courts to suits that interfere with political branch management of foreign affairs, that undermine executive branch efforts to protect the nation's security, and that force courts to usurp the constitutional power of the political branches to decide which norms of international law should be binding and enforceable," he says.

Lawyers for Alvarez-Machain counter that the statute's language supports their client. "Dr. Alvarez relies on the plain words of the ATCA and the overwhelming historical evidence that the first Congress intended the federal courts to hear and decide claims of 'torts committed in violation of the law of nations,' " Mr. Hoffman writes.

The case is of great interest to US-based multinational corporations, a growing number of which are being named as defendants in alien tort cases for doing business in countries with repressive governments. The suits allege that the companies are aiding and abetting the human rights abuses of the host government.

"The litigation is often high stakes," says John Niblock, a Washington lawyer who specializes in defending corporations named in Alien Tort Statute cases. "It usually involves inflammatory allegations of human rights violations seeking damages in the millions or billions of dollars."

Jennifer Green of the New York-based Center for Constitutional Rights says alien tort suits are filed against a corporation only when there is evidence of involvement in abuses. "We only go after the corporation where the company directly participated in human rights abuses," she says.

Some analysts say the Alien Tort Statute could complicate the Bush administration's war on terror by subjecting foreign individuals assisting in the detention and questioning of Al Qaeda suspects to potential liability in US courts for alleged human rights abuses conducted in overseas jails and interrogation chambers.

But others say the law could help the war on terror. "Independent lawsuits by victims of terrorist acts can be extremely helpful to the government in its effort to track down terrorists and their sources of funding," says a friend-of-the-court brief filed on behalf of those who lost relatives on Sept. 11. The brief notes that 209 foreign nationals were killed on Sept. 11.