The perils of political talk at work

September 4, 2012, 6:01 PM UTC

FORTUNE – With one political convention over and another just starting, the presidential campaign will dominate not just the news but also many of our conversations until (and after) election day. Of course, some of those conversations are likely to take place at work. Indeed, many business leaders have already started to talk, and on polarizing issues to boot.

We all know about the relatively recent imbroglio over the comments made by the president of Chick-fil-A in opposition to same sex marriage. On the other side of the issue, Amazon (AMZN) CEO Jeff Bezos and his wife MacKenzie have given $2.5 million to support same sex marriage rights on the ballot this fall in Washington state.

Starbucks (SBUX) CEO Howard Schultz has called for corporations to withhold campaign contributions to incumbents in Washington until Congress strikes a long-term debt deal. Of course, this invites the next question: what do you cut? No consensus there.

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In a sense, the Supreme Court has given this activity a green light by way of its Citizens United decision, which held that corporations and unions are like people and have First Amendment rights to make financial contributions. And senior executives who own or run companies have the power to do the same. The board of directors can likely put a stop to this activity if they see the political activities delivering a blow to the business.

So, if these businesses can weigh in, why can’t you? Feel strongly about either candidate? Why not put a political poster on your door? A statement below your address on your e-mail? Blog about it?

While the government may not prevent corporations from speaking up, in words or dollars, most employers can put a stopper on things vis-à-vis their employees. The First Amendment applies only to government staffers, not private sector workers. So, if you work for a private sector employer, you have no First Amendment rights, on or off duty.

That does not mean that private sector employees lack any rights. When it comes to political speech outside of work, some states provide protection either by law or through legal precedent (and, in the case of California, for example, the state constitution).

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But, even in states where off-duty speech is protected, those protections have limits. In most cases, employers have a right to prohibit employees from engaging in political speech that may be attributed to them.

So, employees who engage in political speech outside of their jobs need to be very careful not to include their employers’ names. Indeed, employees would be well advised to make clear that the opinions are theirs alone.

What about political speech during working hours? Do employees have any protection? As a general rule, in most states, private sector employers could say that they want no political speech in their offices. Now, take a breath.

In most states, private sector employers can discriminate against political speech in favor of a particular party or candidate. Why? Most state non-discrimination laws do not include political affiliation as a protected status.

Prohibiting all speech is not practical. And allowing only one view is neither practical nor desirable. Political perspective is a diversity issue. No company can afford to alienate a sizable portion of its employment pool (or customer base).

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So, if you are an employer, you probably want to caution employees on when, where, and how to talk politics, but not to ban it.

If you are an employee, be thoughtful and do not assume you can say whatever you want. You can’t. Think about what you are saying, to whom you are saying it, and when you are saying it.

Jonathan Segal is a partner at the law firm Duane Morris LLP, where he is a member of the firm’s employment, labor, benefits and immigration practice group. This article should not be construed as legal advice.