Yes – a sincere belief that an employee made threats of violence is perhaps one of the strongest defenses available to claims for wrongful termination.  A recent decision from the Ninth Circuit illustrates this principle well.

In Mayo v. PCC Structurals, Inc., the Ninth Circuit Court of Appeals rejected claims for disability discrimination asserted by an employee who made threats of violence in the workplace.  No. 13-35643 (9th Cir. July 28, 2015).  The employee made multiple threatening comments.  He told one employee that he felt “like coming down with a shotgun and blowing off” the heads of a supervisor and a manager.  He told another employee that he planned to “take out management.”  On another occasion, he said that he wanted “to bring a gun down and start shooting people.”  After these threats were reported, the employer terminated the employee.

In his lawsuit, the employee alleged that the employer discriminated against him on the basis of his disability, major depressive disorder.  The court dismissed the employee’s claim for failure to establish a prima facie case because the employee could not establish that he was a “qualified individual with a disability.”  The court explained that:

An essential function of almost every job is the ability to appropriately handle stress and interact with others.  And while an employee can be qualified despite adverse reactions to stress, he is not qualified when that stress leads him to threaten to kill his co-workers in chilling detail and on multiple occasions (here, at least five times).  This vastly disproportionate reaction demonstrated that Mayo could not perform an “essential function” of his job, and was not a “qualified individual.” This is true regardless of whether Mayo’s threats stemmed from his major depressive disorder.

Takeaway:  Employers do not need to tolerate threats of violence in the workplace even if they result from a disability.  As the court explained in Mayo, federal and state anti-discrimination laws do not “require employers to play dice with the lives of their workforce.”