Sen. Rand Paul will sue President Barack Obama and top officials in the National Security Agency over surveillance.
Paul's political action committee, RandPAC, announced plans by the Kentucky senator and potential 2016 presidential candidate to file a class-action challenge on Wednesday.
The suit also will name National Intelligence Director James Clapper, outgoing NSA Director Keith Alexander and FBI Director James Comey.
A firebrand in the Republican Party whose brand of conservatism embraces Libertarian ideals, Paul is an ardent critic of U.S. surveillance programs, which he says infringe on basic civil liberties under the Constitution.
"The Bill of Rights protects all citizens from general warrants. I expect this case to go all the way to the Supreme Court and I predict the American people will win," Paul said in a statement.
Ken Cuccinelli, a former Republican attorney general in Virginia who lost the state's gubernatorial election last fall, will serve as lead counsel.
Matt Kibbe, president of the tea party aligned group FreedomWorks, also joined the lawsuit, saying any American with a phone should be invested in his case.
"This class action suit isn't about Republican versus Democrat, or progressive versus conservative. This is about defending the basic civil liberties of every American from a government that has crossed the line," he said. "Never in American history has there been such a warrantless gathering of citizens information. We believe it is time to put this before the courts."
National security leaks about bulk NSA collection of telephone and email data exposed by former agency contractor Edward Snowden last year outraged libertarians, privacy advocates and many members of Congress from both sides of the aisle.
They considered it government overreach in the fight against terrorism.
Obama has defended the programs, but announced modest reforms to NSA's practices.
In a speech at the Justice Department last month, Obama revealed new guidance for intelligence-gathering as well as changes intended to balance what he called the nation's vital security needs with concerns over privacy and civil liberties.
Paul joins a number of anti-NSA activists who are unsatisfied with the proposed changes.