As Chris White noted in the LawNewz guide to voting selfies (and those replying to Trump’s tweet astutely pointed out), taking a photo of your ballot is illegal in New York. Trump was clearly using a New York ballot. Manhattan Judge P. Kevin Castel ruled on Thursday that the ban was not a violation of the First Amendment, writing that those who want to publicize their choice have ” “other powerful means” of doing so. The law in question is over 100 years old and specifically bans showing a finished ballot to other people. It is not clear if the Board of Election is actually enforcing the law, we are researching that.