The White House’s mishandling of the Environmental Protection Agency is turning that agency from a usually reliable source of information into one more political-spin operation. Reports this week that the administration had again blocked the completion of a study for a Senate bill to reduce pollution and the agency apparently misled its sponsors about what a preliminary analysis had found demand an investigation in the Senate.

The bill, by Sens. John McCain and Joseph Lieberman and co-sponsored by Sen. Olympia Snowe, requires the reduction of the greenhouse gas carbon dioxide in many areas of the economy, but allow a cap-and-trade program, in which polluters could buy and sell rights to emit more gases. A similar proposal was successfully used to reduce acid rain. The administration, which opposes this bill and others that would set tougher mandatory limits on the amount of carbon dioxide emitted, has a weaker plan called Clear Skies that is much friendlier to industry.

Earlier this summer, the EPA was found to have held back documents that analyzed a bill sponsored by Sen. Thomas Carper of Delaware, which would reduce power plant emissions of sulfur dioxide, nitrogen oxide and mercury earlier and by larger amounts than would the president’s bill. The documents were not made available to the senator but were leaked to the press, apparently by EPA staff members unhappy with the administration’s decision to withhold analyses of comparisons to Clear Skies. The documents show the proposal by Sen. Carper would cost a negligible amount, increasing electricity prices by two-tenths of a cent per kilowatt-hour over the Clear Skies plan, while by 2020 resulting in 17,800 fewer premature deaths from power plant air pollution and saving $140 billion a year in health costs.

The McCain-Lieberman bill apparently would have the same kinds of benefits, but when the senators asked then EPA Administrator Christine Todd Whitman in June about completing an economic impact analysis of their bill, she refused and pointed them toward an analysis done by the Energy Information Administration, saying, “I would expect, based on past analyses, that EIA’s cost estimates should not be significantly different from the estimates that EPA would have produced.” The information leaked to the press this week shows this was not true. Instead of the significant costs shown by the EIA, the preliminary EPA findings found relatively slight cost increases – the EIA estimated a $106 billion cost by 2025; the EPA, $1 billion to $2 billion by that time.

The Senate – beginning with the Governmental Affairs Committee and its chairman, Sen. Susan Collins – should want to know why the large discrepancy exists between the numbers and why the EPA is being discouraged from completing and releasing its work. It should want to know why Ms. Whitman, with access to the preliminary EPA numbers and the public EIA account, would suggest that they were similar when they were not at all alike. It should demand to know why the agency is impeding the work of Congress.