From your very own article you helpfully linked, it was found that he was spreading false information about (text) voting, causing anyone who didn't know better

From your very own article you helpfully linked, it was found that he was spreading false information about (text) voting, causing anyone who didn't know better to become disenfranchised, a violation of their rights as an American citizen and absolutely prosecutable if you want a country based on laws, justice, and equality. Quoted from the article: "As proven at trial, between September 2016 and November 2016, Mackey conspired with other influential Twitter users and with members of private online groups to use social media platforms, including Twitter, to disseminate fraudulent messages that encouraged supporters of presidential candidate Hillary Clinton to 'vote' via text message or social media which, in reality, was legally invalid."