(CNN) George Conway, the husband of counselor to the President Kellyanne Conway, embraced a position on Monday that he's slyly promoted on Twitter for weeks -- his support for Robert Mueller's legal authority in the Russia investigation.

Conway defended Mueller's ongoing investigation as constitutional in a column he published Monday on the national security and legal blog Lawfare. Its title: "The Terrible Arguments Against the Constitutionality of the Mueller Investigation."

The column comes one week following President Donald Trump's tweets called Mueller's appointment "unconstitutional" and after indicted former Trump campaign chairman Paul Manafort tried repeatedly to cut into the special counsel's authority, with no success yet.

Over the almost 3,500-word essay, Conway argues how the Justice Department gives the special counsel powers to investigate and prosecute crimes and describes how both Congress and the courts have empowered such investigations. He sets up his argument in direct response to the President's tweets.

Conway then attacks the law professor Steven Calabresi, who's argued that Mueller has acted outside the Constitution. Calabresi "paints Mueller as a rogue prosecutor run amok: He bizarrely accuses Mueller of" leaking, Conway writes on Lawfare. "In support of all these serious charges and other censorious claims, Calabresi cites nothing."

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