The White House seems poised to issue a revised executive order restricting visas from seven terrorist havens until sufficient vetting procedures are in place. Yet one related issue has not been fully explored: The way the arguments over the original order may have been sabotaged in the Ninth Circuit Court of Appeals.

On its way to upholding an injunction issued against the original executive order, the Ninth Circuit failed to even discuss the relevant federal immigration provision that authorized the president’s action.

At oral argument, the government was represented by career lawyer August Flentje. As Paul Mirengoff at Powerline says, Flentje “did not argue effectively” — an understatement, according to my sources.

But why was Flentje arguing the case in the first place instead of Acting Solicitor General Noel Francisco, an exceptional lawyer who has argued numerous cases before the U.S. Supreme Court and who filed an outstanding brief in the case?

Because on the day before oral argument, Francisco recused himself from the case.

He did so because an attorney from the New York office of Francisco’s former law firm, Jones Day, filed an amicus brief on behalf of several law professors in the Ninth Circuit. That brief questioned the constitutionality and “rationality of the Executive Order” as well as its alleged “discriminatory impact.”

The filing of an amicus brief is not unusual. But the circumstances surrounding this particular brief are unusual and raise ethical questions that have not been answered.

Donald Trump was a client of Jones Day throughout his entire presidential campaign. In fact, his lead lawyer and former Jones Day partner Don McGahn is now the White House counsel.

After Trump was elected president, it is my understanding that he continued to be a client of the firm. Numerous Jones Day lawyers apparently worked on the transition team while still employed at Jones Day until Inauguration Day.

I know for a fact that many of the executive orders signed by President Donald Trump were drafted during that interim period by the transition team, and I have little doubt that this particularly executive order was probably reviewed by Jones Day lawyers.

Yet after they left the firm and joined the administration, a Jones Day lawyer filed a brief taking a position arguing that the signed executive order was unlawful.

Mirengoff and I had an in-depth discussion about this with one of the leading legal ethics experts in the country, who could not understand how Jones Day could allow Feder to file a brief taking a position that was adverse to the firm’s former client.

He cited to District of Columbia Rule of Professional Conduct 1.9 and an accompanying comment:

A lawyer who has formerly represented a client in a matter shall not thereafter represent another person in the same or a substantially related matter in which that person’s interests are materially adverse to the interests of the former client unless the former client gives informed consent.

This disqualification rule is imputed to all members of a law firm under Rule 1.10(a).

All states have almost identical rules.

Meir Feder, who filed the brief, works in the New York office of Jones Day. Rule 1.9 of the New York Rules of Professional Conduct is identical to D.C. Rule 1.9. This means that all Jones Day lawyers are barred under the professional rules of conduct from taking a position that is “materially adverse” to the position of a former client like Donald Trump — unless Trump gives his consent. There is no indication that any such consent was even sought before Feder filed his amicus brief.

The Jones Day firm therefore needs to answer some very serious questions.

When did Donald Trump stop being a client of the firm? Were Jones Day lawyers involved in providing legal advice, legal review, or legal drafting of the executive order in question? If so, why did Jones Day take a legal position adverse to the interests of its (we assume) former client? Did Meir Feder seek permission from the conflicts committee within Jones Day before filing this amicus?

I’ve known many of the lawyers in the Washington office of Jones Day, including a number who have left the firm to take positions within the new administration. All of them are highly qualified, highly ethical, and very professional lawyers.

In the end, having the acting solicitor general argue the case instead of an unprepared lawyer might not have made a difference with this particular Ninth Circuit panel.

But the firm should publicly respond to this ethical issue and explain how, given these facts, one of its New York lawyers acted within the professional code of conduct that governs the behavior of all attorneys when he made what Francisco called a “last-minute filing” in the Ninth Circuit.