Two sections of the Patriot Act, the law Congress passed shortly after the terrorist attacks of Sept. 11, 2001, and a section from a related intelligence law are set to expire Thursday night unless lawmakers vote to extend them. Majorities in both chambers are apparently willing to approve extending them for four years.
But Senator Rand Paul of Kentucky, a libertarian-leaning Republican elected last year, is blocking a hurry-up vote to do so. He wants the Senate majority leader, Harry Reid, Democrat of Nevada, to first allow a vote on several proposed amendments, including a measure that would exempt gun records from being searched under the Patriot Act.
Mr. Paul and Mr. Reid blamed each other for the standoff. If the Senate cannot speed up its usual process for debating bills, the chamber will not be able vote until Friday morning. The House would then still need to approve the bill before it could be sent to President Obama, who is visiting Europe, to be signed into law.
Mr. Reid said Wednesday night that he was working on an agreement that would allow some amendments to be considered Thursday before proceeding to the final vote.
If there is a lapse, a senior administration official said, the F.B.I. would be able to continue using orders it had already obtained, but it would not be able to apply for new ones if further tips and leads came in about a possible terrorist operation. The official, who spoke on the condition of anonymity, reacted with alarm to that prospect, saying no one could predict what the consequences of a temporary lapse might be.
“This is unprecedented,” the official said. “We don’t believe the risk is worth it.”
The three sections that may lapse allow investigators to get “roving wiretap” court orders allowing them to follow terrorism suspects who switch phone numbers or providers; to get orders allowing them to seize “any tangible things” relevant to a security investigation, like a business’s customer records; and to get national-security wiretap orders to monitor noncitizen suspects who are not believed to be connected to any foreign power.
The standoff led to a harsh exchange Wednesday. Mr. Reid accused Mr. Paul of putting the country at risk with “political grandstanding.” Mr. Paul accused Mr. Reid of breaking a promise to allow a full debate over the Patriot Act, which he portrayed as a threat to constitutional rights.
“We don’t want our records to be sifted through by a government without judicial review,” Mr. Paul said. “They don’t want to vote on this because they know the American people agree with us.”