By Lester Rosen, ESR President & Thomas Ahearn, ESR News Blog

Some experts believe that an emerging trend of women as workplace killers may be indicated by recent cases including a September 2010 incident in which a woman allegedly killed coworkers at the baking plant in Philadelphia where she worked after being suspended from her job.

A story on The Philadelphia Inquirer website about the incident reveals that  although women commit fewer than 5 percent of homicides and assaults in the workplace – and are much less likely to kill than men as a rule – several high-profile cases of women killing in the workplace have occurred in the past few years.

  • February 2010: A female professor was accused of killing three colleagues and wounding three others after being denied tenure at a university in Alabama.
  • March 2010: A female supermarket worker in Florida fired for threatening to kill a coworker returned to work and made good on her threat.
  • January 2006: A female former U.S. Postal Service employee killed six colleagues and then herself at a mail-sorting plant in California.

These past cases, combined with the most recent case in Philadelphia, could indicate a possible trend emerging of women committing more acts of workplace violence, according to some experts on the subject.

A teacher at the FBI Academy and author of books on crisis management and violence is quoted as asking “Is it too early to call it a trend, or is it just an anomaly?” in the Inquirer story, adding that he “cannot recall a one- or two-year period in which we’ve had as many women with multiple victims.”

In addition, a study by the University of Tennessee included in the story found that women – although they make up more than half the U.S. population – committed only 15 percent of homicides,  showing that they are much less likely to kill than men. When women do kill, the same study also found they are more likely to choose more “personal” targets such as spouses, intimate acquaintances, or relatives.

According to the U.S. Bureau of Labor Statistics, there were 521 workplace killings in the United States in 2009, 420 of them committed by gunfire. The bureau did not have information on how many were committed by women.

While the term  “workplace violence” is appropriate for a quick definition or diagnosis of a problem, fully defining all aspects of  “workplace violence” can be nebulous at best. Many employers loosely define workplace violence as:

  • Assaults, other violent acts, or threats which occur in or are related to the workplace and entail a substantial risk of physical or emotional harm to individuals, or damage to company resources or capabilities.

While this definition covers a fair degree of actions, a better interpretation should be used in order to create an effective, defensible policy for employers. A better definition of workplace violence should account for the type of offense, circumstance — where and when an incident occurs, and whether it is considered to be “on-the-job” — and party or parties involved. Workplace violence can take place anywhere employees are required to carry out a business-related function.

While many acts of workplace violence are caused by external parties, such as robbery in the workplace by a stranger, recent concerns over workplace violence center on workplace violence carried out by existing employees. These internal incidents of workplace violence leave employers largely liable for any problems that occur in the workplace under the “Negligent Hiring Doctrine” dictating that employers can be held liable for damages if they knowingly employ persons known to pose a potential threat to co-workers or the public.

That said, the question arises — how can an employer identify a potentially problematic employee? The problem is that there is no magic formula that tells an employer in advance who will and will not be violent. Predicting future violence is a matter of considerable controversy. However, experts have found some factors that are present in many cases of workplace violence. One important factor is a history of past violence.  For that reason, pre-employment background checks are widely regarded as an effective screening procedure because the process serves three major functions:

  • First, screening job applicants can bring to light problems in a potential hire’s past such as a history of violence, harassment, or extremely inappropriate behavior.
  • Second, by making it standard policy to screen all job applicants on their way into the company, employers demonstrate due diligence, showing that all reasonable efforts have been made in determining whether or not the applicant poses a threat to the company or to the public.
  • Third, pro-actively communicated background screening practices cause applicants to opt-out by discouraging prospective jobseekers with criminal or problematic backgrounds from applying.

However, there is more to preventing workplace problems than screening at the door. Lives of employees can change. A person who checked out in an initial screen may over time develop the traits or behaviors indicative of a potentially violent employee. It is up to the employer to maintain a constant eye on conditions and events in the workplace — to stay aware of employee attitudes and concerns in order to ensure the safety and security of everyone involved.

For more information about background checks and workplace violence, visit Employment Screening Resources (ESR) at