(3/24/2004) - Should an HMO be held accountable if it refuses to pay for necessary medical care? That’s the question to be decided by the U.S. Supreme Court in Aetna Health Inc. v. Davila and Cigna Healthcare of Texas v. Calad. The issue involves whether injured patients have the right to sue their HMOs in state courts. Insurers argue that HMOs are immune to these lawsuits under federal law.