The problem of workplace bullying landed in the spotlight in October after Miami Dolphins offensive lineman Jonathan Martin claimed he had been singled out for race-based bullying on a number of occasions and left the team. Now, the Dolphins may face one or more legal claims arising from the alleged behavior.

Employers can be liable for claims associated with bullying because the conduct is often related to one or more legally protected characteristics, e.g., a bullying victim’s race, disability, religion, sexual orientation, etc.

Bullying is more common than most people realize. A 2010 study by Zogby International study showed that 35 percent of American workers experienced bullying now or at some point in their careers. In 2012, the Society for Human Resource Management reported that 51 percent of the employers it surveyed had incidents of bullying in their workplaces.

Employee-to-employee bullying can occur in various ways, including insults, the spreading of rumors, unwarranted criticism, exclusion from meetings or other workplace activities, exclusion from “off the clock” social gatherings, pranks and unreasonable work demands, among other things.

The cost to employers due to bullying is real. It’s no surprise studies show that bullied employees tend to be less productive than other workers. Other consequences include high employee turnover, excessive absenteeism and more frequent schedule change requests, all of which add to an employer’s human resources responsibilities and hurt efficiency.

Additionally, employers often see their insurance premiums increase due to more workers’ compensation claims filed on behalf of the bullied employees.

For all of these reasons, employers can (and should) proactively protect themselves against the legal risks of workplace bullying. Here’s how: