Want to share your vote with the world? Don't do it by photo unless you are sure of the laws in your state.

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There is something momentous about voting. Whether it's your first time to the polls, or there's a ballot measure you care about deeply, or you just feel proud to have a chance to exercise this right, standing in that voting booth can feel very significant. And, as we tend to do these days with such moments, you may find yourself wanting to document it, to pull your phone out of your pocket and snap a picture of your marked-up ballot.

Of course the next step is to take that picture and shout it to the world. "I voted for gay marriage!" or "I voted for Barack Obama!" or, simply, "I voted!" And the way this is accomplished, as we all know, is to tweet it, Facebook it, or Instagram it for all to see.

But before you do that, you should know that doing so -- whether merely using your phone in a polling place or broadcasting your posting your ballot photos -- is illegal in much of the country. As Jeff Hermes of the Citizen Media Law Project explains, "Many states have statutes that prohibit the display of one's own marked ballot to others. A small number of these states only prohibit disclosure of one's ballot in the voting room or prior to submission of the ballot, but most impose a flat prohibition on disclosure backed up by criminal penalties or cancellation of the vote in question. These statutes by their explicit terms appear to ban sharing of a photograph of one's ballot even after the election is over." Most of these laws date to a pre-cell-phone era, and quite probably their drafters never foresaw our quotidian photo sharing of today.

Breaking these laws can carry a hefty fine and even jail time, Lois Beckett of ProPublica reports. In Colorado, violators can be fined up to $1,000 or be sentenced to a year in county jail, or both. (To check what the prohibitions are where you live, you can visit the Citizen Media Law Project's Documenting the Vote 2012, which has a work-in-progress chart tracking the different regulations state by state.)

How are these prohibitions not a violation of the First Amendment? Why does the government have the right to tell people not to share a picture of how they have voted, when, quite obviously, you have the right to tell people that exact same information?

As the Citizen Media Law Project describes, the free-speech interests in this case must be weighed against "state interests of the highest order" which in this case are "well-recognized." In the past, the Supreme Court has recognized two compelling reasons for the government to curtail campaigning near polling places. Those reasons -- "protecting voters from confusion and undue influence" and "preserving the integrity of its election process" -- "appear to remain compelling in the context of ballot disclosure laws," writes Hermes. "Display of a marked ballot to voters waiting in the queue can be used as a form of pressure to vote similarly, or to confuse voters who have difficulty reading English as to how to mark their own ballots." Additionally the state has an in interest in preventing vote-buying schemes that ask people to provide photographic proof of their votes in exchange for money.

Even given these interests, Hermes writes that there are "serious concerns as to whether [these prohibitions] are narrowly tailored to meet those interests." If the concern is confusion, why not allow people to share their ballots after the election is over? (Some states already time-limit their prohibitions in this way.) Of course, that still leaves open the vulnerability to vote-buying, but Hermes says that states could just outlaw that practice outright, without "sweeping in a wide array of innocent speech by those who did not sell their votes."

These prohibitions are another example of how our legal regime is struggling to account for communications technologies it never anticipated. It's a messy process, bringing our laws up to speed. For now, you're probably best off just Instagramming your 'I Voted' sticker. Not as cool, but definitely legal.