Chief U.S. District Judge Thomas F. Hogan rejected requests from lawmakers and Rep. William Jefferson to return material seized by the FBI in a May 20-21.
The overnight search was part of a 17-month bribery investigation of Jefferson, a Louisiana Democrat.
In a 28-page opinion, Hogan dismissed arguments by Jefferson and a bipartisan group of House leaders that the raid violated the Constitution's protections against intimidation of elected officials.
Hogan acknowledged the "unprecedented" nature of the case. But he said the lawmakers' "sweeping" theory of legislative privilege "would have the effect of converting every congressional office into a taxpayer-subsidized sanctuary for crime."
The search created a firestorm on Capitol Hill with Democratic and Republican leaders complaining it was a violation of the separation of powers, CBS Radio News correspondent Bob Fuss reports.
A member of Congress is bound by the same laws as ordinary citizens, said the judge, who had approved the FBI's request to conduct the overnight search of Jefferson's office.
Jefferson had sought the return of several computer hard drives, floppy disks and two boxes of paper documents that FBI agents seized during the 18-hour search of his Rayburn Building office.
Hogan said the Justice Department can retake custody of the materials, which President Bush ordered held by the solicitor general until Congress and the agency could work out procedures for future raids on congressional offices.
Jefferson's lawyer, Robert Trout, said he was not surprised by the ruling and would appeal as soon as possible. Trout is expected to ask Hogan to stay his ruling to keep the materials away from investigators until an appeals court looks at the case.
"While a congressman is not above the law, the executive branch must also follow the law," Trout said. "We appreciate the consideration the judge accorded our motion for the return of the seized property, but we respectfully disagree with his conclusion."