No, it isn't. It might be unconstitutional if mandatory voting required you to choose between a fixed number of candidates, but there's nothing stopping voters from putting whatever they please on their ballots.
You are legally compelled by the government to fill out tax paperwork every year. Being (much more lightly) compelled to fill out a ballot is no different.
You are only legally compelled by the government to fill out tax paperwork if you experience a taxable event in that year which would require you to fill out the form. If you do not have a taxable event (i.e., no income) you are not required to send any information to the government in relation to taxes.
The point is that the government can compel speech without endangering the first amendment. The IRS could decide tomorrow to mandate a form for those below the taxable level without running afoul of compulsion.
If your income is subject to taxation, you can't refuse to fill out the paperwork on the grounds that doing so lends legitimacy to an institution you don't support. The same should be the case for voting.
What would be the requirement to compel voting? Be of voting age population and be mentally sound? Sounds like a massive expansion of state power to force all people of a certain age and sound mind to do an action.
I'm not sure what you mean by the "requirement." In order to vote in the US, you have to be of voting age. Some states impose additional requirements, like not being a felon (which I think are wrong, but that's another story).
Mandatory voting would have the same requirements. Anybody who previously could vote now must.
In terms of state power: it's not all that great of an expansion. If you make over the taxable limit, you pay federal taxes. If you own any sort of land, there's a good chance you pay local taxes on it. These sorts of compulsions apply to (equally?) large swathes of the population without necessitating a great deal of state power.
There is a massive difference between paying taxes when you choose to participate in an economy than having the government compel you to make a political statement. You choose to buy land which is protected by the state. You choose to buy things at the store. You choose to have an income. You can choose to not buy a house, you can choose to not work for an income.
The closest thing to compare compelling people to vote would be the draft.
Do people who experience taxable events (possibly without consciously choosing to do so, e.g., inheriting money or property) lose their First Amendment rights? How?
If you chose to not take the inheritance, you would not experience the taxable event. You are not compelled to take an inheritance, the probate courts would absolutely love to take the propery if you do not want it.
It is very different. Compelling one to fill out a ballot (even if it is blank) decays the right to vote into the obligation to vote. Paying taxes is an obligation. Choosing whether or not to vote is a right.
It’s also just a general bad idea. Turnout is a measure of the validity of an election result and support for the democratic process. That’s lost (no, blank and absentee does not send the same message).
What you want is to make it easy to vote, and encourage it. Remove registration requirements. Make sure it never takes more than 15 minutes. Make sure it’s easy to know/find/access the polling place. Make elections be on holidays or sundays.
"Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances."
You could probably write the law in a way that avoids first amendment implications. For instance, require that people show up at a polling place, but do not require them to submit a ballot.
Have an empty spot you can vote for. So they still have to go through the steps and send it in, but they don't actually have to speak/vote on something
This may be dependent on a country's tradition, but voting is not speech, it is one's most direct participation in democracy. Who doesn't vote ignores the system and thus (in my humble and personal opinion) is not a part of it.
In my opinion I don't think it's enough to let people leave their ballot blank because I think that participating in the election process is a form of speech supporting the institution.
To me it is definitely a political statement to abstain from voting or abstaining from the political process entirely so its only logical that participating is also a political statement.
That would be favoring one form of speech (voting) over another. You just have to make people want to vote without directly giving or taking something away from them for it.
You are legally compelled by the government to fill out tax paperwork every year. Being (much more lightly) compelled to fill out a ballot is no different.