1. Generally, the First Amendment does NOT guarantee “freedom of speech” rights at work. Thus, employers may have policies banning purely political discussions and activity, and may want to do so to avoid potential discrimination, harassment or retaliation claims.
2. However, state laws may allow certain political activity protections such as providing time off to vote and precluding the influence of employees' votes - or like in Colorado, an off-duty conduct law.
3. Additionally, the National Labor Relations Act prevents employers (whether unionized or not) from restricting employees' discussions about terms and conditions of employment, which may include some political nexus – such as a candidate's view about wages or working hours.
4. If employees' communications and activities have a nexus to the workplace or occur during non-work hours and/or outside the workplace, employers may not restrict them.
5. If employees' communications and activities are strictly political, including displaying/distributing pollical materials, employers may ban them in the workplace.