President Donald Trump‘s tendency to fire people investigating him should result in his impeachment if it continues, according to former White House ethics attorney, Walter Shaub.

During a discussion on CNN Wednesday morning, Shaub was asked to comment on Trump’s earlier tweet directed at Robert Mueller‘s leaked question regarding the James Comey firing.

In that tweet, Trump cites Fox News legal analyst Joe diGenova wherein he essentially claims that firing Comey cannot qualify as obstruction of justice because the president has the Article 2 power to fire executive branch employees at will and without cause. Shaub said:

What an outrageous tweet. The man seems to think he’s king, not president. It is true he has the power to fire anybody he wants…but what he’s really declaring with that tweet is the idea that a president can go around expressly firing people to prevent himself from being held accountable under the rule of law.

Shaub then referenced Trump’s interview last year with NBC’s Lester Holt. During that interview, the president said:

He [Rosenstein] made a recommendation, he’s highly respected, very good guy, very smart guy. The Democrats like him, the Republicans like him. He made a recommendation. But regardless of recommendation, I was going to fire Comey … And in fact when I decided to just do it, I said to myself, I said ‘you know, this Russia thing with Trump and Russia is a made-up story, it’s an excuse by the Democrats for having lost an election that they should have won’.

The Holt interview was characterized in the following way by Shaub, “He did that with Comey and went on TV and admitted publicly that that was his reason–that he didn’t like being investigated.”

Shaub continued, “Whether or not this is a crime, if he continues to go down this road and fire people for investigating him, how many will it take for Congress to wake up and make a decision that the rule of law in this country matters and the president isn’t above that rule of law? The penalty, if he goes around repeatedly firing people who are investigating him, should be impeachment.”

[image via screengrab/CNN]

Follow Colin Kalmbacher on Twitter: @colinkalmbacher

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