Attorney General Alberto Gonzales on Tuesday defended the FBI's search of a congressman's office last month, saying it was an "unusual step" but a necessary one.

Gonzales compared the May 20-21 search of Rep. William Jefferson's office to past investigations of federal lawmakers and searches of their homes and vehicles.

The late-night search, part of a months-long bribery investigation of the Louisiana Democrat, was the first time in the history of Congress that a search warrant had been executed on a House member's Washington office.

"There have been searches before by the executive branch of the legislative branch," Gonzales said. "We've searched before the homes of members of Congress. We've searched before the cars of members of Congress, even when they are parked in the garage on Capitol Hill."

Among the lawmakers most recently served with search warrants were then-Sen. Robert Torricelli, D-N.J., in connection with allegations of receiving improper gifts, and then-Rep. Randy "Duke" Cunningham, a California Republican whose homes and boat were searched. In August, the FBI raided Jefferson's homes in Washington and New Orleans, and his personal vehicle.

Last month's search of Jefferson's Capitol Hill office sparked outrage from congressional leaders, who claimed the Bush administration was violating the separation of powers doctrine. President Bush ordered the documents sealed until mid-July to allow congressional leaders and the Justice Department to discuss what to do with them.

Gonzales, in Cleveland to award an anti-gang grant, said the search did not violate the Constitution because there was evidence of a crime in Jefferson's office and FBI agents had obtained a court-issued search warrant.

"I understand this was an unusual step that was taken, but it was an unusual step taken in response to an unusual set of circumstances," Gonzales said. Investigators tried for months to get the evidence in other ways, he said, "and we ultimately concluded that this was something that we needed to do."

FBI agents carted away computer and other records in their pursuit of evidence that Jefferson accepted hundreds of thousands of dollars in exchange for helping set up business deals in Africa. Jefferson, who represents most of New Orleans, has denied any wrongdoing.

"I understand the sensitivities," Gonzales said. "We anticipated that this would create some concerns. We worked hard to allay those concerns in the way the search was conducted."