ASHINGTON, Nov. 3 — In a case of potentially great significance for managed-care companies and their patients, the Supreme Court agreed on Monday to decide whether health maintenance organizations can be sued for damages for refusing to cover necessary medical treatment.

The court granted appeals by two managed-care companies that do business in Texas, where a state law, the Texas Healthcare Liability Act, provides compensatory and punitive damages against H.M.O.'s for coverage decisions that are found to amount to malpractice.

A federal appeals court, ruling in both cases, allowed suits against Aetna Health and Cigna HealthCare of Texas to proceed in state court under the statute. The question for the Supreme Court is whether such suits conflict impermissibly with federal law and are therefore barred.

The federal law, the Employee Retirement Income Security Act of 1974, or Erisa, governs employee benefit plans through which more than 130 million people receive their health coverage. Given the Congressional deadlock over patients' rights and the absence of new federal legislation that addresses the evolution of managed care since 1974, states have increasingly stepped into the breach to add protections and remedies. That has made Erisa, with its broad but confusing language that pre-empts some state laws, a focus of litigation. A series of recent Supreme Court decisions has done little to clarify matters, as demonstrated by the fact that the lower federal courts disagree on the basic question that the two new cases pose.

In one of those cases, Aetna Health Inc. v. Davila, No. 02-1845, a patient with arthritis and other medical problems was given a prescription for an anti-inflammatory medication, Vioxx, by his doctor. But Aetna, which provided the medical and prescription coverage for the company where the patient, Juan Davila, worked, authorized Vioxx only for patients who had first tried and failed to benefit from two less expensive drugs. As a result, Mr. Davila took Naprosyn, an alternative that causes a higher incidence of gastrointestinal bleeding.

After three weeks on Naprosyn, Mr. Davila suffered extensive internal bleeding and was taken to an emergency room, where doctors told him that he had come within hours of dying. He needed seven units of blood and was in critical care for five days.

In the other case, Cigna HealthCare of Texas Inc. v. Calad, No. 03-83, Ruby Calad had a hysterectomy along with other surgical procedures. Although the coverage under her husband's health-care plan, provided by Cigna, specified a one-day hospital stay for a hysterectomy, Ms. Calad's surgeon recommended a longer stay. But Cigna's hospital-discharge nurse refused to authorize it. Ms. Calad left the hospital, suffered complications and returned several days later to the emergency room.

Both patients sued for damages in state court, and the companies had the suits transferred to Federal District Court in Dallas, arguing that Erisa covered the cases and that they should be dismissed. The district court agreed. But the United States Court of Appeals for the Fifth Circuit, in New Orleans, ruled last year that the plaintiffs were entitled to proceed in state court under the Texas law.

The appeals court drew a distinction between the Erisa remedy, which it said was limited to reimbursing patients for expenses that under managed-care contracts they should not have incurred, and the damages available under the Texas law for negligence. Because the state remedy did not duplicate the Erisa remedy, federal law did not pre-empt it, the appeals court said.

In their Supreme Court appeals, the companies said the appeals court had ignored the statute's language and Supreme Court precedents that made it clear that Congress intended the Erisa breach-of-contract remedy to be exclusive, not to be supplemented by state remedies.

Among the other developments at the court on Monday were these:

Consumer Testing Suit

Without comment, the court refused an appeal by Consumers Union of a ruling requiring the organization to stand trial in a "product disparagement" suit brought by the Suzuki Motor Corporation.

An article in 1988 in Consumer Reports, a magazine that Consumers Union publishes, said the Samurai, a small sport utility vehicle, "rolls over too easily" based on tests at the Consumers Union test track. The magazine repeated the evaluation in 1996, and Suzuki, which had stopped selling the Samurai in the United States, sued.

In Federal District Court in Los Angeles, the company said Consumers Union had knowingly manipulated the test in 1988 and used the inflammatory result to increase its magazine circulation. The court dismissed the case before trial, but the United States Court of Appeals for the Ninth Circuit, in San Francisco, overturned the dismissal and ruled that Suzuki was entitled to have its case before a jury.

The question for the Supreme Court in the appeal here, Consumers Union v. Suzuki Motor Corp., No. 03-281, was what standard an appellate court should apply in reviewing a grant of summary judgment in a libel case against a public figure. The product-disparagement claim was a subset of libel, and under the First Amendment, libel against a public figure can be proven only by a "clear and convincing" demonstration of knowing or reckless falsity.

Consumers Union argued that in reinstating the suit, the Ninth Circuit had failed to apply this "actual malice" standard with sufficient rigor and had looked just at isolated facts, not the whole record. It argued, as had the dissenting judge on the Ninth Circuit, that letting the suit proceed would invite similar suits against consumer groups by manufacturers vexed by product ratings.

The Ten Commandments

As expected, the court refused to hear an appeal by Roy Moore, the suspended chief justice of Alabama, of lower federal court orders requiring the removal of a Ten Commandments monument from the rotunda of the state's judicial building. The Supreme Court's refusal to grant an emergency stay paved the way to remove the monument and indicated that the justices would not hear the case. Mr. Moore had filed two appeals, In re Moore, No. 03-258, and Moore v. Glassroth, No. 03-468.

Wilderness Policy

The court accepted an appeal by the Bush administration in a case over regulating off-road vehicles in federal wilderness areas in the West. The Southern Utah Wilderness Alliance and other environmental groups sued in 1999, arguing that the failure to limit the vehicles' use violated federal laws. The question for the Supreme Court in Norton v. Southern Utah Wilderness Alliance, No. 03-101, is whether the federal courts have jurisdiction to consider such a claim before an agency has announced a final policy.