In its fumbling attempts to explain the purge of United States attorneys, the Bush administration has argued that the fired prosecutors were not aggressive enough about addressing voter fraud. It is a phony argument; there is no evidence that any of them ignored real instances of voter fraud. But more than that, it is a window on what may be a major reason for some of the firings.

In partisan Republican circles, the pursuit of voter fraud is code for suppressing the votes of minorities and poor people. By resisting pressure to crack down on “fraud,” the fired United States attorneys actually appear to have been standing up for the integrity of the election system.

John McKay, one of the fired attorneys, says he was pressured by Republicans to bring voter fraud charges after the 2004 Washington governor’s race, which a Democrat, Christine Gregoire, won after two recounts. Republicans were trying to overturn an election result they did not like, but Mr. McKay refused to go along. “There was no evidence,” he said, “and I am not going to drag innocent people in front of a grand jury.”

Later, when he interviewed with Harriet Miers, then the White House counsel, for a federal judgeship that he ultimately did not get, he says, he was asked to explain “criticism that I mishandled the 2004 governor’s election.”