Should you—can you?—fire employees for complaining about work-related issues online?

Unfortunately, the latest report on the subject doesn't answer that with certainty. It does suggest you need to consider carefully whether you're breaking the law if you do go ahead and pink-slip someone for, say, a Twitter rant about you.

The National Labor Relations Board, the federal agency that enforces labor law, has reviewed 129 cases since 2009 that involve social media and the workplace. Most of those cases were filed this year, according to a study released by the U.S. Chamber of Commerce, the nation's largest business lobbying group. (The number of complaints filed increased sharply when the NLRB said in October that American Medical Response of Connecticut was wrong to fire an employee for criticizing her boss on Facebook.)

The report's conclusions: The issue most commonly raised in the cases is that an employer has "overbroad policies restricting employee use of social media or that an employer unlawfully discharged or disciplined one or more employees over contents of social media posts."

The policies alleged overbroad, not surprisingly, were those that restrict discussion of wages, corrective actions and discharge of co-workers, employment investigations, and "disparagement of the company or its management."

Observed the report: "The context in which the policy was adopted and even the issue of whether a rule or policy has been actually adopted are also important in these cases."

When it comes to disciplining or firing an employee based on social media, the key issues are whether comments on Twitter, Facebook et al are protected under the 1935 National Labor Relations Act, which lets employees discuss working conditions. (The NLRB has yet to set a policy on this.) Also at issue is whether an employer has unlawfully threatened, interrogated, or checked up on employees.

Nancy Cleeland, an NLRB spokeswoman, told Bloomberg the board has almost finished its own report on social media charges that "should provide useful insights" for employers in crafting policies on the subject.

Stay tuned. 

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