A political candidate's firing in Florida offers a reminder of a little-understood fact of American life: Companies have sweeping discretion to effectively regulate what their workers do outside of work, including running for elected office.

That startling reality resurfaced after Marriott Vacations Worldwide came under fire for terminating Viviana Janer, a senior manager who is also the Democratic nominee for a seat on the Osceola County Commission. "I think it's a stinking maneuver to rob her of her job and rob the voters of their votes," Democratic Congressman Alan Grayson charged this week. Janer says her candidacy is consistent with the company's support for civic participation; her employer, a time-share company spun off from Marriott International in 2011, says it threatened a conflict of interest.

In a September 19 termination letter, Marriott Vacations wrote that Janer had been given the choice to either resign from her campaign or resign from her job. "She was given those two options," confirms Edward Kinney, a vice president of the company, "and she chose not to do either one."

The company's move may be controversial, but there's nothing obviously illegal about it. In fact, as I've noted before, U.S. workers can be fired for all kinds of activities outside of work: volunteering for the AIDS Foundation, using medical marijuana, even just driving around with a John Kerry bumper sticker. There are some clear exceptions. Firing someone for practicing a religion or organizing a union during their time off is illegal. But aside from Montana, neither state nor federal laws require that private sector companies have a good reason for firing people.

Few states require that terminations have anything to do with work performance. According to a 2010 review by the National Conference of State Legislatures, only four states have statutes broadly protecting workers from being fired for (non-criminal) things they do outside for work. Seventeen states offer specific protections for after-hours tobacco users, and another eight protect using lawful products.

The First Amendment protects free speech and the right to petition the government, but it only restricts the government from trampling those rights—it doesn't ban your boss from punishing you for exercising them.