John McCain just signaled he doesn't trust Republicans alone to investigate Trump

On Wednesday Sen. John McCain (R-Ariz.) called for a select committee to investigate ties between President Donald Trump's 2016 campaign and Russia.

"No longer does the Congress have credibility to handle this alone," McCain told MSNBC, "and I don't say that lightly."

Unlike the current congressional investigation being conducted by the Republican-controlled House and Senate committees, a select committee investigation would be overseen by equal members of both parties, giving Democrats more say in the process. 

McCain's comments come just a few hours after House Intelligence Committee Chair Devin Nunes (R-Calif.) held a press conference outside the White House where he alleged that the intelligence community had taken "inappropriate" measures in investigating the Trump campaign — though in the same appearance also affirmed that all of their actions were legal.

Shortly after Nunes' comments, Rep. Adam Schiff (D-Calif.), the ranking Democrat on the House Intelligence Community, made his own media appearance in which he expressed frustration with Nunes' comments as well as his decision to brief the White House on the subject before his fellow committee members.

"The chairman will need to decide whether he is the chairman of an independent investigation into conduct, which includes allegations of potential coordination between the Trump campaign and the Russians," Schiff said, "Or if he's going to act as a surrogate of the White House, because he cannot do both."

Democrats in the House and Senate have variably called for either a select committee, an independent commission or a special prosecutor to investigate allegations of collusion between the Trump campaign and Russia.

McCain's call indicates he does not trust an investigation conducted at the direction of his own party, which has an interest in protecting the president. Previously, McCain's close ally Sen. Lindsey Graham (R-S.C.) has said he was open to supporting a select committee if news reports about contact between the president's campaign and Russia proved to be true.

Clearly, his friend and colleague John McCain has seen enough.