Nominated for several Academy Awards, the movie The Social Network was one of the cinema hits of 2010. In real life, millions of users turn to Facebook at all times of the day about all sorts of matters, both personal and business. But how far can employees go in commenting about work-related matters?

The legal boundaries are slowly being drawn. In a new case, the National Labor Relations Board (NLRB) jumped to the defense of an employee who was allegedly fired for posting derogatory comments about her supervisor online. The case was recently settled out of court.

Facts of the case:The NLRB accused American Medical Response (AMR) of Connecticut of illegally firing one of its employees. In a Facebook post, the employee claimed that her supervisor had prevented her from having a union representative present while she responded to customer complaints. Her coworkers made supportive comments about her post.

However, the online remarks included certain vulgarities, as well as this comment, “Looks like I’m getting some time off. Love how the company allows a 17 to be a supervisor.” A 17 is the code that the company uses for a psychiatric patient.

After the employee was fired, the NLRB issued a complaint against AMR. It alleged that the firm engaged in unfair labor practices by firing the employee for making the online comments. The NLRB also asserted that AMR’s policy concerning Internet postings was vague and overly broad.

Key point:Under the National Labor Relations Act, employers cannot enforce policies that impede an employee’s right to discuss wages, working conditions or unionization. In this case, the NLRB argued that criticism of a supervisor, as part of a discussion with coworkers, is protected activity under the Act—even if the communication takes place on a social media Web site such as Facebook.

For its part, AMR maintained the employee was not fired because of the online comments. Instead, it claimed that termination resulted from complaints about the employee made by patients and hospital staff. The employee had requested that a union representative be present during an investigation of those complaints by AMR, but the request was denied. It was at this point that the employee was fired. AMR characterized the firing as being due to her “rude and unprofessional conduct.”

The NLRB also objected to the broad terms in AMR’s handbook concerning online postings and blogs by employees. In particular, the agency took notice of one section of the handbook that said, “Employees are prohibited from making disparaging, discriminatory or defamatory comments when discussing the Company or the employee’s superior, coworkers and/or competitors.” A spokesperson for the NLRB cited this section as being vague and conflicting with fundamental labor laws that allow employees to criticize supervisors and discuss employment matters with coworkers.

Final outcome:According to media reports, AMR has agreed to change the policy that prohibits workers from posting disparaging comments about supervisors. It will also amend its rules concerning company depictions over the Internet.

The relationship between media sites such as Facebook and the workplace will continue to evolve. Both employers and employees should take notice of new developments in this area. Your professional advisers can help you adapt your company policies—including making revisions in handbooks and manuals—to meet the changing needs.