Realistically, if the President/Vice President were both incapacitated and the Speaker of the House was from an opposing party, what would happen?

Replying to my own question…

I think it must. Nobody would expect the Speaker to have to resign from Congress if, say, the President and VP just went on a weekend ayahuasca retreat or something. So, if he/she doesn’t have to resign from Congress immediately, I don’t see any logical point at which it should become mandatory.

Which makes me think of yet another point: If the Speaker of the House becomes acting President, does that mean “the person who is serving as Speaker of the House at the time the Presidency becomes vacant” or “whoever is currently serving as Speaker of the House”? If the Speaker became acting President, could Congress elect a new Speaker and transfer the Presidential powers to them? I’m thinking not, because in practice obviously the Speaker would have to resign from Congress in order to do an adequate job of Presidenting, and it would be paradoxical for them to then lose the Presidency as well.

If there is only an “acting” President in power, would that mean that Congress could theoretically make anyone they wanted (who is Constitutionally eligible) President just by amending the Presidential Succession Act to make it so?

That’s what it used to say, and created uncertainty with the death of Harrison, as you point out.

The 25th Amendment, s. 1, made it explicit:

Section 1 . In case of the removal of the President from office or of his death or resignation, the Vice President shall become President.

True - and the same ambiguity exists today for everyone in the line of succession except the VP. My expectation is that the ambiguity would be resolved the same way as happened with Harrison/Tyler - the Speaker (or whoever) would assert that they are the President, whole and complete, and that would eventually be accepted, and become a new precedent (a President precedent)

No, because the Presidential Succession Act says that the speaker has to resign to exercise the duties of Acting President:

19(a)(1) If, by reason of death, resignation, removal from office, inability, or failure to qualify, there is neither a President nor Vice President to discharge the powers and duties of the office of President, then the Speaker of the House of Representatives shall, upon his resignation as Speaker and as Representative in Congress, act as President.

(My bolding)

P.S. Back when it looked like Nixon and Agnew would both be out of office, the US came close to having a Speaker (Carl Albert - Wikipedia) become President via succession. The plan Ted Sorenson prepared for Albert (https://ir.lawnet.fordham.edu/cgi/viewcontent.cgi?article=1004&context=twentyfifth_amendment_watergate_era) inclulded resigning from the House, and remaining in office until 1977

Good catch! Thanks.

Yes, there can be.

Suppose the Prez, Veep, Speaker and Prez pro tem are all on the crash of Air Force 1 and die. Then the Secretary of State becomes Acting President under s 19(d)(1).

The House reconvenes and elects a Speaker. Ta-dah! The new Speaker is higher in the list and becomes Acting Prez, as set out in s. 19(d)(2):

(2) An individual acting as President under this subsection [19(d)] shall continue so to do until the expiration of the then current Presidential term, but not after a qualified and prior-entitled individual is able to act, except that the removal of the disability of an individual higher on the list contained in paragraph (1) of this subsection or the ability to qualify on the part of an individual higher on such list shall not terminate his service.

Doesn’t “prior-entitled” rule out a new Speaker? Seems like the prior means that if President A and VP B are in comas, Speaker C is President until/unless A or B recovers - but no one else can take C’s place

I’m guessing the Speaker of the House becomes acting president until the next scheduled presidential election, since there is no provision in America for snap elections the way France or Japan does it. So if, say, this scenario happened in April 2025, the Speaker would be president until January 2029 when the newly elected prez and VP take office.

It is written like that in the Presidential Succession Act of 1947. I’m guessing acting president since a President can only be removed by impeachment/conviction. But let’s say the Speaker is only 34 years old. Under the law they cannot be acting President but on their 35th birthday they can remove the acting President and take on the role.

I’m not sure it would work that way. Section 6 of Article 2 says

No Senator or Representative shall, during the Time for which he was elected, be appointed to any civil Office under the Authority of the United States, which shall have been created, or the Emoluments whereof shall have been encreased during such time; and no Person holding any Office under the United States, shall be a Member of either House during his Continuance in Office.

So, it appears that one can either be Speaker of the House/President Pro Tempore of the Senate, but, if required by the 25th Amendment to become Acting President, has to leave that post during the time they take over the office of the President.

As for a Speaker of the House removing an Acting President, Section 2 of the 25th Amendment says

Whenever there is a vacancy in the office of the Vice President, the President shall nominate a Vice President who shall take office upon confirmation by a majority vote of both Houses of Congress.

Now we’re in the murky territory of whether the Acting President’s “powers and duties” include nominating a new Vice President. Or, for that matter, whether Congress or the Supreme Court could order the acting President to do so. Or, for that matter, could Congress impeach and convict an “Acting President” for failing to nominate a new Vice President.

And just to extend the hypothetical, suppose the office of the Speaker were vacant and the President Pro Tempore were serving as Acting President. Would a newly elected Speaker then automatically become Acting President?

Maybe that is precisely the significance of the “acting” modifier, that an acting President can’t nominate a new Vice President. I’ve certainly never heard anyone suggest that this could or would happen if (for example) the Speaker became acting President; the assumption always is that the Speaker would keep the job until the next election.

To the hypothetical in your last sentence: according to Northern Piper’s cite a few posts up, I think so. It would be a case of “the ability to qualify on the part of an individual higher on (the) list”. By virtue of becoming Speaker, the new Speaker would “qualify”.

That’s a really badly written law. One could argue that the antecedent of “his” is the bolded part at the beginning, which would make it mean the opposite of what the legislators presumably intended to mean, that such an individual’s service as Acting President won’t be terminated if someone higher on the list becomes available.

Not necessarily, because that clause only applies to members of the House or Senate, but the Speaker doesn’t actually need to be a member of the House. It always has been, but that’s just a matter of custom, not of law.

In a regular presidential term, maybe even in Trump’s first term I’d say yes. If POTUS and VPOTUS were both brain dead on ventilators (with no chance being unplugged). There’d be griping, maybe even attempts broker a comprise where the house speaker resigns in favor of a more palatable candidate. But ultimately it would get invoked on both of them

In the current administration? Hell no. The primary qualifying factor to be admitted to the current cabinet is to agree to never under any circumstances invoke the 25th amendment.

Normally the Presidential Succession Act should kick in whether or not the 25th is invoked explicitly if the POTUS/VP are obviously and visibly rutabagaed — but that would only mean that no matter what there will ensue some intense shouting and shoving before SCOTUS and the learned Justices are not going home until they rule.

But wouldn’t they be nominating their own VP, and not one to succeed the dead Pres.?