The General Accountability Office, Congress' investigative branch, has reported that the Bush administration illegally allowed private health plans in a Medicare trial to limit some participants' choice of health-care providers. The trial of private plans utilized preferred provider organizations (PPOs), a form of health insurance popular among senior citizens.

The GAO reported Monday that in some cases Medicare participants' costs were not covered by the PPOs if the beneficiary used a health-care provider other than that selected by the PPO. The GAO concluded that the Bush administration granted exceptions to PPOs, despite a requirement that the plans cover the costs of any health-care services in a recipient's package. The American Association of Preferred Provider Organizations has more on PPOs. The New York Times has more.