The roughly 3,400-word article published Monday on the respected Lawfare blog was largely a rebuke to Calabresi, who argued in his May 13 op-ed that the special counsel had exceeded the constitutional limits established in a 1988 Supreme Court case.

The critique came as a rebuttal of a Wall Street Journal op-ed by conservative scholar Steven Calabresi, disputing the special counsel's constitutionality. It is not the first time Conway has taken issue with his wife's boss.

George Conway, lawyer and husband of White House counselor Kellyanne Conway , just wrote a forceful defense of special counsel Robert Mueller 's Russia investigation. It's the latest in a series of less-than-subtle digs the conservative has taken against President Donald Trump .

In his opening salvo, Conway said Calabresi's op-ed may have influenced Trump's thinking on the legal validity of the probe when he tweeted in early June "the appointment of the Special Counsel is totally UNCONSTITUTIONAL!"

Trump tweet

Conway saved some of his most direct criticism for Trump himself.

"It isn't very surprising to see the president tweet a meritless legal position," Conway concluded, "because, as a non-lawyer, he wouldn't know the difference between a good one and a bad one."

Conway argued that the Mueller investigation has not exceeded its authority under the Appointments Clause of the Constitution, and challenged Calabresi's assertion that the special counsel is acting like a "principal officer," which Calabresi said would violate the Supreme Court's precedent.

In a yet-to-be-published response defending his stance on Mueller, Calabresi said Conway "mangles" his argument and "fails to confront the overwhelming evidence that the Mueller appointment is unconstitutional."

The White House did not immediately respond to CNBC's request for comment.

Kellyanne Conway has swatted away questions about her husband's criticism of the president she directly serves, saying in a CNN interview in April that asking about his social media use is "meant to harass and embarrass."