At a Senate Judiciary Committee hearing Tuesday, Sen. Charles Schumer asked Attorney General Eric Holder (above) about the Bush administrations role in approving gun walking. The House Oversight and Government Reform Committee is investigating a Justice Department operation that resulted in assault weapons getting to Mexican drug cartels.
House Democrats have also used the investigations as an opportunity to plug Democratic policy priorities.
Waxman and DeGette, for instance, urged Energy and Commerce Chairman Fred Upton (R-Mich.) to expand the Solyndra investigation into examining whether the U.S. can effectively compete on clean energy internationally.
At other times, when the worst headlines hit, Waxman, Cummings and other top Democrats have gone quiet.
Last week, Lanny Breuer, assistant attorney general for the Justice Department's Criminal Division, conceded he knew that federal officials allowed weapons to fall into the possession of Mexican drug cartels as early as April 2010, about 10 months before the department denied to Congressional investigators that the investigative strategy was used.
Breuer expressed "regret" for not alerting other top officials about the tactic when it "became public." Cummings did not address Breuer's admission the week it was made. Through a spokeswoman, Cummings said, "It was appropriate for Lanny Breuer to testify before Congress, and he apologized for not flagging these problematic Bush administration programs earlier."
Republicans also flag a personnel connection among the Democrats. Dave Rapallo, a top aide to Cummings, was previously a lawyer for Obama's National Security Council. Before that, he worked for several years for Waxman, including as his chief investigative counsel and as general counsel for the Energy and Commerce Committee.
"It's as if they have one playbook on obstructing oversight, and both committee minorities are methodically working their way through it," said Frederick Hill, a spokesman for Issa.
But the Democrats defending Obama from the investigations are sensitive to the need to maintain credibility.
"I'm not here to defend Solyndra. I'm not here to defend the administration," DeGette said.
"A few months ago, I met with Brian Terry's family. Brian Terry, of course, was a Border Patrol agent who was killed. And two guns from Fast and Furious were found at the scene. I promised them two things. One, that we would get answers for him. Two, that this would never happen again," Cummings said Oct. 16 on CBS' "Face the Nation."
From the Democrats' perspective, Republicans have so overreached on their investigations that their two duties — oversight and party — haven't even been in tension.
"Credibility is all you really have when all is said and done on investigations," Waxman said, referring to what he called Republicans' lack of credibility.
"The way this investigation has been conducted, it's been a vehicle for attacking the administration," DeGette said, calling the scope of Upton's request for White House documents "shocking."
Issa "comes up with these statements, and then he goes in search of the facts," Cummings said on "Face the Nation."
On the question of whether the investigations had turned up anything troubling, DeGette and Waxman parted.
"We don't have enough evidence to say," DeGette said. But she continued, "Was this just the cost of doing business? Seems like a high cost."
Waxman said the $525 million loss to taxpayers was part of taking risks on clean energy technology.
"It's one of those unfortunate results that maybe can be predicted on occasion. I think most of the loan guarantees have been successful," he said. "But there are some that are inevitably not going to be successful, and this is one of them."
Former Sen. Scott Brown, R-Mass., candidate for U.S. Senate in New Hampshire, holds his hand over his heart during the singing of the national anthem as he waits to take the stage for his town hall campaign rally with Sen. John McCain at the Pinkerton Academy in Derry, N.H., on Monday, Aug. 18, 2014.