By Charles Lane

A Bush administration lawyer urged the Supreme Court to uphold the authority of federal agents to make arrests abroad and to curtail the rights of foreigners to sue the U.S. government or corporations for human rights violations abroad, in a pair of cases the administration has called crucial to its ability to fight terrorism and drug trafficking.

Deputy Solicitor General Paul D. Clement told the court that U.S. law enforcement would be crippled by a federal appeals court's rulings in favor of a Mexican doctor who alleges he was kidnapped in Mexico by the U.S. government and one of its Mexican agents.

Those rulings, Clement said, "turn the established separation of powers regime for dealing with issues of international law on its head," giving the judiciary more foreign-policy power than the executive branch and precluding "federal agents from making arrests abroad even when foreign governments consent."

At issue are the Federal Tort Claims Act (FTCA) and the Alien Tort Statute. The first one provides for lawsuits against the federal government for alleged personal injuries, while the second has been interpreted by courts to permit suits in U.S. courts for alleged torture or other violations of international human rights law abroad.

Humberto Alvarez-Machain, a Mexican doctor seized in the slaying of U.S. Drug Enforcement Administration agent Enrique Camarena -- but later acquitted by a federal court -- says his arrest in Mexico was illegal. He sued the U.S. government under the FTCA, and Jose Francisco Sosa, the Mexican who seized him on the United States' behalf, under the Alien Tort Statute.

Last year, the U.S. Court of Appeals for the 9th Circuit, based in San Francisco, ruled that Alvarez-Machain could sue the United States because drug enforcement agents have no authority to carry out arrests on foreign territory, and that he could sue Sosa because the "arbitrary" arrest violated international law.

The Bush administration and Sosa are supported by business groups and foreign governments, which see in the case an opportunity to end litigation against them spawned by the Alien Tort Statute, a 1789 law that a federal appeals court interpreted in 1982 to permit human rights lawsuits.

In their view, the law, which says that "district courts shall have original jurisdiction of any civil action for an alien for a tort only, committed in violation of the law of nations or a treaty of the United States," did not create a right to sue.

U.S. corporations have been the target of recent lawsuits that seek damages for alleged collaboration in human rights abuses in such countries as Burma and apartheid-era South Africa.

"There are too many cases creating too much havoc for no good reason," Sosa's attorney, Carter G. Phillips, told the court. "Enough is enough."

Alvarez-Machain is backed by human rights organizations that say the Alien Tort Statute has evolved into a powerful tool for holding accountable wrongdoers who would otherwise be outside the reach of law.

They note that, in more than two decades, no federal court has held otherwise -- and the executive branch supported that view until the Bush administration. In the background of the case is concern that, during the current war against terrorism, the United States may make common cause with foreign governments and individuals whose actions may run afoul of international law.

Upholding the 9th Circuit's judgment "will not undermine national security. It will only uphold the values that made this country great," Alvarez-Machain's attorney, Paul Hoffman, told the high court.

Because these cares are so complicated, the court held 90 minutes of argument instead of the usual hour. But the justices' questions gave little indication of how they might ultimately rule.

Justice Sandra Day O'Connor hinted she thinks the court could uphold the government's authority to arrest terrorists abroad without ruling on the Alien Tort Statute.

"I wonder if it isn't wise to look at the statutory grounds used by the 9th Circuit and let Congress deal with the law," she observed to Clement.

The cases are Sosa v. Alvarez-Machain, No. 03-339, and U.S. v. Alvarez-Machain, No. 03-485. The court is expected to rule by July.