Good old principled Rand Paul

Sen. Rand Paul (R-Ky.) blocked a resolution calling for special counsel Robert Mueller's report on the Russia probe be made public, marking the fifth time Republicans have blocked the House-passed measure.

Sen. Mark Warner (D-Va.), the vice chairman of the Senate Intelligence Committee, asked for unanimous consent on Thursday to pass the resolution, which cleared the House in a 420-0 vote earlier this year.

"What we're talking about is basic transparency, let's make sure the full Mueller report is released to Congress … and then let's make sure the American people see as much of this report as possible," Warner said from the Senate floor.

He added that to warn future campaigns and candidates about potential election interference "we need to fully understand what the Russians were trying to do."

Under Senate rules, any one senator can request that any bill or resolution be passed. But because it requires the signoff of every senator, any one senator can also block their request.

Paul objected because Warner wouldn't agree to amend the nonbinding House-passed resolution to include provisions calling for the public release of communications between several Obama-era officials including former President Obama, former FBI Director James Comey and former CIA Director John Brennan.

Paul argued that Congress still needs to figure out the "entire story" including the origins of the investigation into President Trump's campaign and a controversial research dossier compiled against then-candidate Trump.

"I think it's very important that we not turn our country into this back and forth where each successive party tries to use the apparatus of government to investigate the previous president," Paul said.

"What we don't know is was President Obama told that the evidence to get this investigation started was paid for by the Hillary Clinton campaign? We need to know that," Paul continued.

Paul has warned that he would block the resolution backing the Mueller report's release unless information about the opposition research dossier compiled against Trump was also released. He first blocked the House-passed resolution last week.

"It was so scandalous and so unverified and has turned out to be untrue, and yet this was the basis for the beginning of the investigation. This was the basis for doing something extraordinary," Paul added on Thursday of the dossier. 

A 2018 memo from the House Intelligence Committee, which was controlled at the time by Republicans, found that the FBI's counterintelligence investigation into whether Trump campaign officials had improper contacts with Russia was triggered by information the bureau obtained about George Papadopoulos, a former adviser to the campaign.