Expressing yourself with the "like" feature on Facebook is no longer grounds for getting fired. The 4th U.S. Circuit Court of Appeals is overruling a lower court decision in the case of a former deputy sheriff in Hampton, Virginia. He claimed he lost his job for "liking" the Facebook page of the Sheriff's candidate running against his former boss.
The appeals court decision states that "Liking a political candidate's campaign page" is the "Internet equivalent of displaying a political sign in one's front yard." Putting up a sign is something the Supreme Court has ruled as protected speech. The lower court said the deputy's use of the Facebook "like" feature was not substantial enough to protected by the First Amendment.