Sen. Charles Grassley on Friday stepped up his dispute with the White House over Operation Fast and Furious, as three of his Judiciary Committee investigators were provided to bolster Grassley’s claim that President Barack Obama’s spokesman was wrong Thursday about the fight over documents. …

Grassley, a critic of the Justice Department and FBI under both the Bush and Obama administrations, rejects the Obama White House assertion that Grassley is motivated by partisan politics.

“The accusation that I’m motivated by a desire for a ‘political scalp’ is baseless,” Grassley said in his written statement.

“(N)one of these limited communications between Mr. O’Reilly and Mr. Newell revealed the existence of any of the inappropriate investigative tactics at issue in your inquiry, let alone any decision to allow guns to ‘walk,'” wrote Ruemmler in a letter to the offices of Rep. Darrell Issa (R-Calif.) and Sen. Charles Grassley (R-Iowa). Citing Executive Branch confidentiality interests, Ruemmler said, “There is an insufficient basis to support the request to interview Mr. O’Reilly.”

If Justice Department documents that Issa’s committee seeks from Attorney General Eric Holder had been the subject of a top-secret meeting in the White House Situation Room, their contents already would have been splashed across the media. Issa could read the A1 New York Times story and be done with it.

Now, if documents aren’t handed over—which, sources say, include Holder’s emails—the full House will likely vote on holding Attorney General Holder in contempt.

Meanwhile, though these missing emails may or may not be as damning as the missing minutes were on the Nixon tapes, we should remember that it took almost eight months for the Watergate scandal to bust wide open into a national news story.

Then Congress should look into the overall flow of firearms from the United States into Mexico. The Fast and Furious weapons were just a small part of a much larger problem. Mexican officials have complained for years that lax U.S. gun laws have the effect of worsening drug-related violence along the border. The damage done by cocaine, marijuana and methamphetamine smuggled north across the border is mirrored by the damage done by guns smuggled south.

If Issa really wants to save U.S. and Mexican lives, he should convene hearings on banning the sale of high-powered weapons. I think Holder would be happy to testify.

Perhaps it’s true, as the White House has argued, that Mr. Issa’s investigation has degenerated into a partisan fishing expedition. And perhaps yielding to that would discourage candor in the councils of this and future administrations, as the Obama administration, echoing a standard plea of its predecessors, asserts.

But Congress’s authority to gather information is broad — as broad as its sweeping powers to legislate, spend public money and hold executive officials accountable through impeachment. No doubt a lot of congressional investigations are partisan fishing expeditions. For better or worse, that comes with the democratic territory. Absent very strong countervailing considerations — stronger than some of those the administration has asserted in this case — Congress is generally entitled to disclosure.

[T]he House could use its power of the purse. It could threaten to cut funding to the bureau running the Fast and Furious program or to the Justice Department as a whole. It could even refuse to pay Holder’s salary until he purges his contempt. Lower down the scale of confrontation, the House could pass a resolution censuring him or continue to hold hearings designed to embarrass him.

The House risks looking petty in doing any of this, just as the Obama administration risks looking petty by withholding information from Congress. As with all high-level conflicts over the separation of powers, whoever can win public opinion will ultimately win the day. And that is as it should be; after all, these people are competing to be our public servants. It is a fundamentally political contest and should be settled by political means.