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President Obama's decision to assert executive privilege over Operation Fast and Furious documents not only failed to delay contempt proceedings against Attorney General Eric Holder -- it raised a whole new line of constitutional questions and challenges about the power of the presidency.

Republicans already are seeking more than 70,000 additional documents to answer their existing questions on Fast and Furious. The executive privilege claim opened up a new avenue of probing.

The immediate question was whether the documents contained information so damaging that the president was willing to risk the bad PR by moving to lock them down. GOP lawmakers also questioned whether Obama's assertion was legitimate, later voting in committee that it was not appropriate in this case. And Republicans repeatedly suggested that the White House had tipped its hand, and acknowledged being involved in Fast and Furious discussions by asserting privilege over the documents in question.

"He's either part of it or he's not," Rep. Trey Gowdy, a feisty Republican lawmaker from South Carolina, challenged during Wednesday's committee meeting on Holder. "If (Obama's) part of it, then we've had a series of witnesses that have misled this committee. And if he's not part of it, then he's got no business asserting executive privilege."

House Speaker John Boehner's spokesman also said the move "implies" the White House was involved in the operation itself or the coverup.

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Following up, Sen. Chuck Grassley, R-Iowa, sent a letter to Obama Wednesday asking for a "more precise description" of the executive privilege claim. He asked whether Obama was extending the claim to documents pertaining to "communications with you," or to Justice Department communications separate from the White House.

The White House and Justice Department, though, downplayed the potential implications of the executive privilege claim.

Justice Department officials noted that the assertion does not have to pertain to communications involving the president or White House staff. Any "deliberative communications" among officials in the Executive Branch, they said, could be covered.

In other words, they argued that just because Obama is locking down the documents doesn't mean he had anything to do with the Fast and Furious discussions.

Executive privilege has been invoked 24 times since the presidency of Ronald Reagan. This was Obama's first time asserting it.

Republican lawmakers, who so far have been given 7,600 documents, are looking specifically for information from February 2011 and beyond that follow a Justice Department letter which erroneously claimed the department did not allow guns to "walk" across the Mexico border.

The department later retracted that claim.

After the House Oversight and Government Reform Committee voted Wednesday to hold Holder in contempt of Congress, committee Chairman Darrell Issa, R-Calif., told Fox News there's still time to avert a floor vote on the contempt resolution. Republicans could abandon the vote if they receive documents which they feel satisfy the subpoena.

Holder is not considered held in contempt unless and until the full House votes.

Both the White House and Justice Department slammed the committee vote Wednesday as political.

Holder, in Denmark, reportedly called the move "unwarranted, unnecessary and unprecedented."