Some congressional Democrats appear concerned that special counsel Robert S. Mueller isn’t being thorough enough in his investigation into President Donald Trump.

Democratic Rep. Adam B. Schiff, Mueller’s No. 1 defender on Capitol Hill, believes Mueller could decline an investigation into the president’s businesses, he told the Los Angeles Times editorial board.

One issue of particular interest to Democrats, Schiff said Monday, was the ongoing negotiations between Trump’s allies and representatives from the Russian government over a skyscraper in Moscow during the 2016 election. (RELATED: Schiff Says Trump May ‘Face The Very Real Prospect Of Jail Time’)

“Anyone who engaged in anything like that, anything remotely like that, would never get a security clearance, but this is the president of the United States,” Schiff told the LA Times. “If the financial entanglement goes beyond that, and includes money laundering and criminal activity that the Russians could expose at a time and place of their choosing, that’s compromising.”

The California representative later expressed concern that “Mueller may not be looking at this,” and said that House Democrats may have to take up the cause.

These concerns could also be why a number of Democrats are supporting impeachment proceedings against Trump before the release of Mueller’s final report.

Democratic Reps. Al Green of Texas and Steve Cohen of Tennessee said on Jan. 3 they would reintroduce articles of impeachment against the president, accusing him of obstructing justice.

Other Democrats, like House Judiciary Committee Chairman Jerry Nadler, a New York Democrat, told CNN on Jan. 4 that members of his party would not wait for Mueller to release his final report before beginning their own investigations.

Despite the president’s criticisms of the special counsel’s investigation, there remains no evidence that Mueller has received resistance from the White House.

Yet Democrats have placed a tremendous amount of political capital into the idea Mueller will eventually uncover damning information that would prove Trump, or those in his inner circle, colluded with the Russian government to change the outcome of the 2016 election. Should that not happen, the president would seem at least partially vindicated in his attacks on Mueller’s investigation.

Democrats, particularly those in the House, have good reason to start their own investigations into the president’s business dealings in order to keep up the pressure should Mueller eventually clear him in his final report.

As the investigation continues, Democrats may also feel pressure to deliver some sort of smoking gun. Speaker of the House Nancy Pelosi, who has generally deferred to the special counsel, recently implied some restlessness among Democrats.

“We won’t interfere,” Pelosi told Politico in October. “We shouldn’t. We won’t. But we do have to have one thing that we should all agree on: the truth for the American people and where the truth leads us is another thing.”

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