From what I remember, state supreme courts have regularly decided that there is no fundamental right to marry. New Jersey noted it in that recent gay marriage event not long ago, at the very least.

You remember wrong. The NJ court noted that the fundamental right of marriage was well-established, but declined to extend that rule to invent a fundamental right to gay marriage, which AFAIK no court has recognized, ever. Traditional marriage as a fundamental right goes back at least as far as Loving v. Virginia, and AFAIK has not been disturbed since (and can’t be by any court other than the USSC).

I believe the 24th amendment exists because there is no explicitly defined right to vote (in fact, Jesse Jackson tried to get an amendment stating the right to vote in 2003), and that the Constitution says that states can legislate the ability of individuals to vote (which is why both the 14th and 15th amendment exist, rather than simply the 14th).

Nonsense. The Constitution doesn’t say anything about an individual’s “ability” to vote, only about the right of U.S. citizens to do so. In four separate amendments, no less, two of which preceded the 24th, which is itself written in terms of “rights” rather than “abilities.” I don’t know where the popular meme about not having a constitutional right to vote comed from, but it could scarcely be more wrong. How many other constitutional rights get four separate mentions in the written Constitution?

A right that can be legislated away is no right at all.

Correction: any right that hasn’t been legislated away is indeed a right, just not a constitutional one. More importantly, even constitutional rights can be legislated some, they just can’t be legislated too much. Absent the 24th Amendment, poll taxes would be like any other taxes with the potential to undermine constitutional rights: unconstitutional if unreasonable or oppressive, but constitutional if it is not.

Also, “poll tax” means a tax per head, not a tax on voting (although this was distorted by racists in the 20th century). The federal government was originally limited to indirect taxes (customs and excise), or a direct tax which had to be allocated among the states according to population, which is a roundabout way of saying a head tax. AFAIK, they tried to collect that just once, to finance the Mexican-American War. Henry David Thoreau refused to pay and went to jail…

Taxes on constitutionally protected rights are not well defined. You’d never get away with a “free speech” tax, but a “right to assemble” can be taxed as anyone trying to rent a decent conference room can tell. The people will pay for the right to an attorney if you aren’t able to pay for one, but you also usually have to pay a small sum of money to get into the public defender groups lists anyway just to cover paperwork. Taxing the right to remain silent… eh, wouldn’t get much favor.

The best constitutional understanding I can figure is that only taxes proportional to the purchase of other items, or directly related to the costs, can be put in place – for example, a 5% sales tax would allow a 5% “assembly” tax, and you can charge minimal costs to get the right to an attorney. But this isn’t well covered or accepted, and I’d personally prefer that our constitutionally protected rights not go by-by because the Fedos need more cash.

I believe the 24th amendment exists because there is no explicitly defined right to vote (in fact, Jesse Jackson tried to get an amendment stating the right to vote in 2003), and that the Constitution says that states can legislate the ability of individuals to vote (which is why both the 14th and 15th amendment exist, rather than simply the 14th). A right that can be legislated away is no right at all.

I’m no lawyer but I’m pretty sure taxing a right is illegal (poll taxes, for example). Thoughts?

That is not correct. Taxing a right so heavily as to effectively prohibit it is one thing, but short of that, there is no general bar on taxing rights. Courts have held, for example, that there is a right to travel, but that does not prohibit any level of government from taxing cars, gasoline, jet fuel, airline tickets, or any other expenses associated with it. Hell, they’ve even invented a separate category of “fundamental” rights, which get more “constitutional” protection than the “ha ha, just kidding” ones, yet no court has ever questioned the power of states to charge a fee and require a license to exercise the “fundamental right” to marry. Poll taxes are the exception that proves the rule: if government were generally prohibited from taxing rights, the 24th Amendment would not have been necessary.