So, I think that this is just political showboating (though I don’t approve of legislators doing this, normalizes it), but to take it more seriously…

My kneejerk reaction is that it’d be unconstitutional, but I’m not sure, upon further thought.

So, there are a couple isssues that I see.

Can you send an American citizen abroad as a form of punishment?

There’s the question of whether this violates the Eighth Amendment’s prohibition on cruel and unusual punishment.

So, exile is definitely unconstitutional. You can’t simply kick an American citizen out of the US and keep them out, and there’s case law supporting that. You can’t take their citizenship away as punishment; that’s an Eighth Amendment violation.

But…you can draft people to the military, and compel people to go abroad. Sentencing someone to six months of service is sort of like that. I don’t know whether there’s case law as to whether that can constitutionally be used as a punishment, however. And I don’t know whether it’s constitutional to compel someone to enter a non-US legal jurisdiction as a punishment, because I can imagine a lot of ways in which one could avoid constitutional restrictions if one could, as part of a sentence, just move someone out of the legal jurisdictions where those restrictions apply.

My guess is that this might be permissible, but I can’t think of actual examples where something like this was done.

Ex post facto laws

The second is whether it amounts to an ex post facto law. Generally-speaking, you cannot make something retroactively-illegal, nor make the sentence more-severe.

I’m pretty confident that this would violate the ex-post-facto restriction, as it specifically applies to past actions as well as future. It might be possible to provide for making doing community service in Palestine as an alternative sentence for someone convicted of a crime. However, this is specific to the portion making it retroactive. Generally, if a law is severable – that is, the remainder of it can reasonably stand on its own – part of it being invalid doesn’t make the whole invalid. My guess is that the retroactive portion of such a law would fail the ex-post-facto restriction, but due to severability, it could still be applied to people who commit a crime moving forward, so would remain partially enforceable.

Safety

Gaza probably isn’t all that safe, and some of the issue with being sent to Gaza might be physical risk. That might run afoul of the Eighth Amendment as well.

So, we do have the death penalty – someone can explicitly be condemned to death. But aside from that, going from memory, there are some constitutional requirements for the conditions in which prisoners may be kept. You can’t just say “you’re going to prison for an N year sentence” and make the prison environment have a 50% mortality rate.

googles

Yeah, there’s Eighth Amendment criteria on prison conditions:

https://www.ce9.uscourts.gov/jury-instructions/node/165

I’m not sure exactly the legal rationale there. It may just be that you cannot have the executive treat a sentence of prison as something akin to a death sentence, can’t basically “upgrade” the severity of a law. It might be okay to do if the legislature’s intent is for the sentence to be dangerous. Could be an issue or not.

Restriction on speech

The First Amendment generally does not let the government criminalize speech. It’s possible to a very limited degree, but compared to virtually all other countries, the US Constitution has a very low tolerance for this.

So, I thought “okay, that’s a sentence for a non-content-neutral speech restriction”, so it’d violate the First Amendment. But…I’m not totally sure about that. Because in this case – and I haven’t looked at the bill text – they aren’t actually criminalizing anything new. The only association with content is the time, that there are currently protests on a particular topic happening. Like, if you were convicted for something unrelated to Israel-Palestine, it’d still apply (and in fact, the article authors complain about this). So I don’t think that it raises First Amendment issues.

That being said, my guess is that there’s some level of sufficiently-close association where linking a crime or punishment to speech even if the link isn’t explicit probably does violate the content-neutral restriction. Like, you can’t go out and come up with criteria that just happens to only punish the people involved in certain speech. But my guess is that this wouldn’t reach that level, given how broad it is.

Overall

My guess is that the ex post facto portion would be struck down as unconstitutional. But I’m not at all sure that the remainder wouldn’t stand, were we to hypothetically assume that it actually were passed and signed into law.