Interesting article in the New York Times:  Nonprofit Hospitals Face Scrutiny Over Practices, by Robert Pear:

Congressional leaders, concerned that many nonprofit hospitals are not providing enough charity care to justify their tax-exempt status, say they will set standards for the industry if it does not do so itself.

The chairman of the Senate Finance Committee, Charles E. Grassley, Republican of Iowa, who had already been examining nonprofit groups like United Way and the American Red Cross, is broadening his focus to include nonprofit hospitals, with an eye to legislation that would clarify standards for their tax exemptions. Representative Bill Thomas, Republican of California, the chairman of the House Ways and Means Committee, began investigating the financial practices of nonprofit hospitals last year. The commissioner of internal revenue, Mark W. Everson, said tax officials often found little difference between nonprofit and for-profit hospitals "in their operations, their attention to the benefit of the community or their levels of charity care."