Kentucky Republican Sen. Rand Paul announced Wednesday that he would filibuster any attempt by Senate Majority Leader Harry Reid to bring the Protect IP Act to a vote.

PIPA, the Senate version of the Stop Online Piracy Act, is being sponsored by Vermont Democratic Sen. Patrick Leahy and pushed by Reid as a “job creator.”

The bills would ostensibly crack down on online copyright infringement, but critics contend that the legislation would also challenge free speech and the ability of large websites to function.

Texas Republican Rep. Lamar Smith, the sponsor of SOPA, announced Tuesday that the bill would continue to undergo markup in the House Judiciary Committee, which he chairs, in February.

An unprecedented online protest by companies opposed to the bills occurred Wednesday. Online encyclopedia Wikipedia, social news website Reddit and the classifieds site Craigslist all blocked their U.S. versions in protest and directed visitors to contact their elected officials.

“Both PIPA and SOPA give the federal government unprecedented and unconstitutional power to censor the Internet,” Paul said in a statement. “These bills enable the government to shut down websites that it deems guilty of violating copyright laws.”

Paul continued: “While we support copyright protections, we are also concerned about websites being shut down without their day in court, and making innocent third parties bear the costs of solving someone else’s problems.

“I will not sit idly by while PIPA and SOPA eliminate the constitutionally protected rights to due process and free speech. For these reasons, I have pledged to oppose, filibuster and do everything in my power to stop government censorship of the Internet,” Paul said.

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