Matthew Whitaker, the acting attorney general, seems like a perfect fit for the Trump administration.

Before Whitaker joined the Trump administration as a political appointee, the Republican lawyer and legal commentator complained that special counsel Robert S. Mueller III’s investigation of Russian interference in the election and of the Trump campaign was dangerously close to overreaching. He suggested ways it could be stopped or curtailed and urged his followers on Twitter to read a story that dubbed the investigators “Mueller’s lynch mob.”

Now — at least on an interim basis — Whitaker will assume authority over that investigation, an arrangement that has triggered calls by Democrats for him to recuse himself.

He also harbors interesting views on the role of the Supreme Court in the scheme of things, arguing that the landmark 1803 Marbury v. Madison case that affirmed the court’s role as the final arbiter of interpreting the Constitution was one of the worst decisions the court has rendered.

“There are so many,” he replied. “I would start with the idea of Marbury v. Madison. That’s probably a good place to start and the way it’s looked at the Supreme Court as the final arbiter of constitutional issues. We’ll move forward from there. All New Deal cases that were expansive of the federal government. Those would be bad. Then all the way up to the Affordable Care Act and the individual mandate.”

He also seems to think that our laws descend from a higher power.

During a 2014 Senate debate sponsored by a conservative Christian organization, he said that in helping confirm judges, “I’d like to see things like their worldview, what informs them. Are they people of faith? Do they have a biblical view of justice? — which I think is very important.”

At that point, the moderator interjected: “Levitical or New Testament?”

“New Testament,” Whitaker affirmed. “And what I know is as long as they have that worldview, that they’ll be a good judge. And if they have a secular worldview, then I’m going to be very concerned about how they judge.”

Religious tests for judges are barred by the Constitution, but I think we already know where he stands on interpreting it.

To round out the rest of the portfolio, as an attorney he’s been accused of defrauding clients.

When federal investigators were digging into an invention-promotion company accused of fraud by customers, they sought information in 2017 from a prominent member of the company’s advisory board, according to two people familiar with the probe: Matthew G. Whitaker, a former U.S. attorney in Iowa.

It is unclear how Whitaker — who was appointed acting attorney general by President Trump on Wednesday — responded to a Federal Trade Commission subpoena to his law firm.

In the end, the FTC filed a complaint against Miami-based World Patent Marketing, accusing it of misleading investors and falsely promising that it would help them patent and profit from their inventions, according to court filings.

In May of this year, a federal court in Florida ordered the company to pay a settlement of more than $25 million and close up shop, records show. The company did not admit or deny wrongdoing.

Whitaker’s sudden elevation this week to replace fired Attorney General Jeff Sessions has put new scrutiny on his involvement with the shuttered company, whose advisory board he joined in 2014, shortly after making a failed run for U.S. Senate in Iowa.

At the time, he was also running a conservative watchdog group with ties to other powerful nonprofits on the right and was beginning to develop a career as a Trump-friendly cable television commentator.

So, he’s got authoritarian-executive views of the basic laws of the country, he wants religious tests for judges, and he’s provided legal counsel to a fraudulent get-rich-quick scheme here in Florida.

My only question is why wasn’t he the first pick for Trump’s attorney general before Jefferson Beauregard Sessions III?

Bonus Track: According to two highly-respected legal scholars, Neal K. Katyal and George T. Conway III, Trump’s appointment of Mr. Whitaker as acting attorney general is unconstitutional.

What now seems an eternity ago, the conservative law professor Steven Calabresi published an op-ed in The Wall Street Journal in May arguing that Robert Mueller’s appointment as special counsel was unconstitutional. His article got a lot of attention, and it wasn’t long before President Trump picked up the argument, tweeting that “the Appointment of the Special Counsel is totally UNCONSTITUTIONAL!”

Professor Calabresi’s article was based on the Appointments Clause of the Constitution, Article II, Section 2, Clause 2. Under that provision, so-called principal officers of the United States must be nominated by the president and confirmed by the Senate under its “Advice and Consent” powers.

He argued that Mr. Mueller was a principal officer because he is exercising significant law enforcement authority and that since he has not been confirmed by the Senate, his appointment was unconstitutional. As one of us argued at the time, he was wrong. What makes an officer a principal officer is that he or she reports only to the president. No one else in government is that person’s boss. But Mr. Mueller reports to Rod Rosenstein, the deputy attorney general. So, Mr. Mueller is what is known as an inferior officer, not a principal one, and his appointment without Senate approval was valid.

But Professor Calabresi and Mr. Trump were right about the core principle. A principal officer must be confirmed by the Senate. And that has a very significant consequence today.

It means that Mr. Trump’s installation of Matthew Whitaker as acting attorney general of the United States after forcing the resignation of Jeff Sessions is unconstitutional. It’s illegal. And it means that anything Mr. Whitaker does, or tries to do, in that position is invalid.