Can US Supreme Court justices / judges be "rotated" out against their will?

Question

In last night's US Presidential Debate, candidate and US Senator Bernie Sanders asserted the option of being able to "rotate" Supreme Court judges / justices to other courts. As quoted in The Hill:

"I do not believe in packing the court," Sanders said during the second of the first two 2020 Democratic presidential debates. "We’ve got a terrible 5-4 majority conservative court right now. But I do believe constitutionally we have the power to rotate judges to other courts and that brings in new blood into the Supreme Court and a majority I hope that will understand that a woman has a right to control her own body and that corporations cannot run the United States of America."

For background, Article III, Section 1 of the US constitution is in full:

The judicial power of the United States, shall be vested in one Supreme Court, and in such inferior courts as the Congress may from time to time ordain and establish. The judges, both of the supreme and inferior courts, shall hold their offices during good behaviour, and shall, at stated times, receive for their services, a compensation, which shall not be diminished during their continuance in office.

Article II, Section 2, states in part:

[The President,] by and with the advice and consent of the Senate, shall appoint ... judges of the Supreme Court, and all other officers of the United States, whose appointments are not herein otherwise provided for...

Is Sanders' claim (in bold above) correct? Does the US President, or anyone else for that matter (other than a Supreme Court justice choosing to retire from their position on the Supreme Court) have the power to "rotate" those judges to other courts?

Consistent with Sanders' claim, this question is asked under the current US constitution assuming no amendments; just about anything is possible via amendment.

Also, while a bunch of folks on Law.SE might be able to speculate or find persuasive arguments posted in answers below, who would be able to authoritatively decide the constitutionality of such a question, with all Supreme Court justices having clear conflict of interest on the matter?

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A couple law professors posts proposals here (and in more detail here, reviewed here), one for a rotating panel of appeals court judges to serve on the Supreme Court, and another for a 15-justice Court with 5 appointed by each party and 5 picked unanimously by those 10, without the ability to hear cases if those seats are empty. There is also a proposal circulating for 18-year term limits followed by remainder-of-lifetime service on a circuit court. If any of those, or other strategies, appear constitutional at present, an explanation of why would be a great answer, as would be an explanation of why any proposal involving rotation consistent with Sanders's quote would not be possible under the current constitution unamended.

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Note: The question framing intentionally excludes consideration of any person or military force who might have the physical firepower to remove Supreme Court justices in a way that would leave them unable to serve as a judge in another federal court. That's not "rotating" off.

Answer 1

I will only address this part of the question:

Who would be able to authoritatively decide the constitutionality of such a question, with all Supreme Court justices having clear conflict of interest on the matter?

The Supreme Court could still hear such a case, as the justices make their own decisions about when to recuse themselves. In particular, they might decide to hear the case based on the "Rule of Necessity", which says roughly that a biased judge is better than none at all: a judge can hear a case, even in the presence of a conflict of interest, if there is no other way for it to be heard. See United States v. Will, 449 U.S. 200 (1980), in which the Supreme Court ruled 8-0 that federal courts could try a case related to the salaries of federal judges.

Another possibility is that the case could be brought in a lower federal court, say District Court. There is a question here: the Supreme Court has original jurisdiction in "all Cases affecting Ambassadors, other public Ministers and Consuls" (US Constitution, Article III, Section 2), and I do not know whether Supreme Court justices are "public Ministers". However, if a lower court did have jurisdiction, it could rule on the constitutionality of the question, since a District Court judge would not have a significant conflict of interest. The relevant Circuit Court of Appeals could presumably hear an appeal. If the Circuit Court's ruling was appealed to the Supreme Court, and the Supreme Court felt that they all had conflicts of interest (and decided not to invoke the Rule of Necessity), then they could simply not vote to grant certiorari, in which case the Circuit Court's ruling would stand.

Answer 2

Sanders is technically correct but practically wrong.

The only way to remove a sitting justice from the US Supreme Court, without that justice's consent, is by impeachment. So what Sanders has proposed could be done; Congress could impeach the longest-serving member of the court, the president could then appoint another to join the court, and if the removed justice were willing the president could appoint him to some other federal court.

However, unless the judge removed in this way had done something genuinely wrong, he/she would probably mount a legal challenge, and the other eight would rule that the procedure was playing the system in order to get around the US Constitution's very clear intention that appointment to the high court is a lifetime affair.

(There's also the point that Sanders' motivation—by his own admission—is to clear away judges who fail to support his ideology. That is not going to win him any fans on the court.)

Answer 3

The question is whether the word "Offices", from Article 3 Section 1, in the case of a sitting Supreme Court Justice (SCJ), refers to their office specifically as SCJ or more broadly as a "Judge, both of the supreme and inferior Courts".

Moving someone between a federal court and the SCOTUS, or between federal courts, is very frequent a precedent : it happens each time the President nominates to a federal Judge position someone who previously was a federal Judge. Such was the case for Ketanji Brown Jackson for example, who was an Appellate Court Judge before and during her nomination as SCJ.

If following this precedent as an example for a "rotation", as Sanders means it, then there's a strong bar against rotating someone against their will : it would require (1) the President's initiative, (2) the agreement from the person, and (3) the consent of the Senate.

However, while the (1) is required by Article 2, Section 2, Clause 2 of the Constitution, the (3) can be waived by Congress, as per the same clause, and the (2) is established by nothing more than precedent. It would seem weird to nominate and Senate-consent someone to a position without the person's consent, but would it be unconstitutional ? It would not be unseen of: for example, prior to the mid-20th century, the Speaker of the british House of Commons could get appointed by the House against his own will.

So, here is what a constitutional "forced rotation" from the Supreme Court to a lower federal court could look like:

1. The President uses their Art. 2 Sec. 2 C. 2 power to nominate a sitting SCJ, say Justice Wilson, to a lower federal court, say the 5th district Court of Appeals.
2. a. Either Congress previously granted such kind of nomination a waiver of confirmation by the Senate, or

2. b. the Senate confirms the nomination of Wilson to the 5th of Appeals

3. The possible refusal of the nomination by Wilson is overridden by, say, an act of Congress setting the procedure for such kinds of nominations (or even by an Executive Order, or by an argument in court saying that it was never necessary?).
4. That act, or the nomination itself, is (most probably) subject to judicial review on whether it is constitutional or not (and I refer you to Nate Eldredge's answer as to how that works).

Under a favorable interpretation of the Constitution, Wilson would, after this process, keep their Art. 3 Sec. 1 federal judicial office, and thus would not contradict the "shall hold their Offices during good Behaviour" clause of the same article. If the judicial review mentioned in my 4. upholds that interpretation, then that would constitute a valid way of rotating a SCJ to another federal Judgeship.

Disclaimer: this is only one interpretation of how that "rotation" could be implemented, requiring presidential initiative for each rotation. Other versions of how a rotation could be done, for example by statutory mandate, are only bounded by your imagination and I can't speculate on their constitutional validity.