The FBI is doing its best to root out corruption on Capitol Hill—Robert Mueller called it the bureau’s “top criminal priority”—but investigators are being thwarted by a new twist on a constitutional provision, the Washington Post reports. The “speech or debate” clause was intended to protect lawmakers from harassing lawsuits and political attacks, but lately its interpretation has broadened.
It began when an appeals court struck down evidence obtained in a raid on William Jefferson’s congressional office. Now, a wide swath of evidence, such as wiretapped conversations with other lawmakers, is deemed out of bounds. Investigations into Tom DeLay, John Doolittle, and Rick Renzi have all slowed to crawls, while Ted Stevens was spared an explicit bribery charge. “It’s the biggest issue in federal corruption prosecutions,” said one former prosecutor.