Under the First Amendment, public employees have the right to speak out on important issues of public concern. As a general rule, your speech is protected if, as a non-policymaking public employee:
The government has an interest in sustaining an efficient workplace, which usually requires disciplining and managing their employees’ speech that is part of the job. Nevertheless, for the law generally prohibits a public employee from having fewer free-speech rights than a private citizen who is not employed by a public agency. Case law aims to balance both of these interests by facilitating First Amendment rights for their employees.