The federal raid on a high-flying firm of defense lobbyists has prompted a few brave Democrats to propose the ultimate reform  an outright ban on the practice of lawmakers’ customizing budget goodies for contractors who requite with generous campaign donations. This circular flow of taxpayer money is at the heart of the investigation into the PMA Group of lobbyists.

The firm was created by a former staff member and protégé of Representative John Murtha, the powerful head of the defense appropriations subcommittee. PMA funneled tens of millions in donations to cooperative lawmakers. Last year, 104 House members earmarked $300 million worth of contracts for PMA clients.

Grateful politicians deny that their gratitude has any impact on their policy decisions  that would be illegal. Members could do away with all suspicions, and any possible temptations, by signing on now to the cold-turkey proposal of two Democrats, Paul Hodes of New Hampshire and Gabrielle Giffords of Arizona. It would bar lawmakers from taking contributions from anyone who benefits from their budget earmarks.

As disruptive as this would be for the Capitol’s quid pro quo as usual, it’s a needed addition to Speaker Nancy Pelosi’s ethics agenda. Some of her members are warning the anticorruption pendulum that secured their majority may be swinging back toward the Republicans.