"It's hard to imagine that while the Russians were actively undermining our election and trying to influence it on Trump's behalf, that regular contact between Trump's team and Russian intelligence officials — it's hard to imagine that had nothing to do with what the Russians were attempting to do with the election," McMullin told The Salt Lake Tribune.
U.S. intelligence agencies have concluded that Russia had attempted to help Trump in the U.S. election, including with the hacking and subsequent leaks of information from Democratic National Committee computers. The latest revelations about Flynn's conversations with the Russian ambassador to the United States after Trump's election to the White House only underscored critics' concerns that an investigation is needed.
Flynn resigned Monday after acknowledging he had misled the White House about his discussions with the Russian ambassador.
The New York Times reported this week that Trump campaign aides and associates had multiple conversations with Russian government officials during the campaign.
White House press secretary Sean Spicer pushed back on the criticism.
"The irony of this entire situation is that the president has been incredibly tough on Russia," Spicer said Tuesday.
Trump himself took to Twitter early Wednesday to complain about the news media coverage of Flynn and directed his anger at leaks by the U.S. intelligence community.
"The real scandal here is that classified information is illegally given out by 'intelligence' like candy. Very un-American!" Trump wrote.
He also complained about information being given illegally to The New York Times and The Washington Post and said that was "just like Russia."
McMullin, who spent 11 years in undercover assignments for the CIA in Southeast Asia, the Middle East and North Africa, said he is still in contact with many "friends" in the intelligence community and they are stuck in a hard spot between their oath to defend the country from enemies both "foreign and domestic" and the law, which forbids sharing classified information.
"In this case, I can tell you that many intelligence officers in the United States are highly concerned about the danger they believe Donald Trump poses to the country," McMullin said.
"It's hard to overstate just how uniquely dangerous this situation is," he added. "We have the president of the United States who may have been compromised by virtue of some of his activities with the Russian government. ... That puts our security and intelligence officials in a very difficult position."
Rep. Jason Chaffetz, a Utah Republican and chairman of the House Oversight and Government Reform Committee, which has broad jurisdiction over the federal government, says he is open to launching a probe of Flynn's actions but has so far declined Democrats' request to investigate the larger question of Russia's attempts to undermine the U.S. election.
McMullin, who also worked as a congressional aide to the House Republican Conference, says Congress must now step in to clear the air about actions by Russia and the Trump team. He suggests a special select committee in the House or Senate — like the one Republicans set up to look at allegations of then-Secretary of State Hillary Clinton's involvement in the attacks on the U.S. consulate in Benghazi, Libya — to get to the bottom of the controversy.
What did the president know, and when did he know it? McMullin says, quoting an oft-repeated line that dates to President Richard Nixon's Watergate scandal. In this situation, McMullin says, the American people deserve to know what was happening behind the campaign rallies, especially given the flow of news about Russia's involvement.