Workplace violence can take place in different forms.  The more common variety of workplace violence is more or less the hazards of the job.   Healthcare workers and emergency medical workers often face abuse.  some of it is physical, but most of it is verbal abuse from ailing and often drugged out patients.    Taxi drivers, retail clerks, and others having to deal face to face with the public are subjected to robberies and battery, sometimes murder.  Law enforcement and security personnel can put their lives in jeopardy, but again these are the hazards of the job.

Another form of workplace violence is when an disgruntled lover, spouse, or whatever decides to take it upon himself to burst into the workplace and verbally or physically abuse the one he so believes had done him wrong.  It's an ugly situation and a bad scene all the way around, often culminating after a period of domestic abuse.  But often it can be spontaneous combustion, the assailant having learned he was being treated to either real or illusory forms of romantic injustice.   Snap out, stalk your significant other, and then surprise her in the workplace, right where she can be the most embarrassed, where her co-workers can see what she has been putting up with for the past umpteen months.  Why her morale has been so low, the bruises, the nervousness that had gradually diminished her performance while transplanting her better persona with one of despair and frustration.  At least, that's how it usually works.

There are the cases where a disgruntled employee decides that whatever is ailing him is more than he can bear and shares it with his co-workers by going on a  rampage and shooting them at will.   "Going Postal," did not become a household phrase, because this, for awhile, was an uncommon occurrence among our fair public servants at the post office.   I could add that shooting rampages were the only time they were ever documented to move quickly, but then I digress.

In the past few years, one case that comes to mind was with a Georgia beer and soda distributor, okay, pop in some parts of the country, where an employee was caught dead to rights on video tape stealing cases of beer for probable resale.  Caught dead to rights, living video color.  Of course, he was fired.  At which point the disgruntled party declared he had been subjected to harsh discriminatory practices and shot up the place, killing several of his fellow workers.  There was the college professor, a couple of years ago, who upon learning she was considered too unstable to be granted tenure proved the point by shooting  up her colleagues.  Several were killed and more were wounded.  Apparently, some years before, the same woman had killed her brother with a shotgun, claiming it was an accident, she had just been cleaning the gun.  She had a history of verbal and physical abuse and yet here she was, teaching at a major university.  The DA's office who originally didn't bring charges on the killing of her brother, has done so since the shooting incident on the college campus.

Thus we have the recent incident or workplace violence in North Carolina, where an employee harbored his grievances until he burst into the workplace and shot and killed three people and wounded two more .  Those trying to escape were gunned down the the parking lot.   According the police reports, his were not random shootings.  He was picking his  victims whom he believed had harassed him on the job.  Apparently, he wrote it down in a six  page letter he left behind, after dying of a self-inflicted gunshot wound.

So with all this crazy stuff, the question is how can an employer prevent it?   In some instances, sadly, you cannot. In other instances, perhaps you can. Background checks can offer you some insight into the making of a job candidate.   But then you are basing you decisions on what a candidate has done in his past.    Someone with a violent criminal past may be  more likely to explode within the workplace  and commit violent acts.   Some may have learned their lessons by suffering the consequences of their past behavior.  But with others, it may well be a reflex.    Common sense would have it that people used to using violence are more prone to resort to violence, to act out when feeling threatened or harassed.  The aforementioned professor comes to mind.  Why no one  flagged her early on may be more a testimony to timidity in the academic environment that failure of an honest evaluation.

But then that is a long way from the answer.  There are many employees who never  committed a violent deed.  But there is always the first time.  There are those who are under pressure from the job, from their domestic strife, from having money troubles, where they finally snap a switch.   Couple the pressure of uncertainty and domestic strife with consequential drug and alcohol abuse and you have a desperate personality who deludes himself into believing a violent outburst has some kind of rational basis.

And then the frustrations find outlet in disturbing ways that make headlines and leave others killed, wounded, or emotionally damaged from what some claim can be an avoidable tragedy.   But then, that term  "avoidable."  With workplace violence on the increase, avoidable is far less tangible than ever before.

So it is wise for employers to have in place a prescribed communications channels where concerned employees can voice their observations.   For employers, make it simple for employees to approach managers about those who are acting strange or who are making threats, especially of a violent nature.     Have a structured procedure so every employee is clear about how the process works.

Managers need to be on the lookout for dramatic behavior modification in their staff.  Those who suddenly become sullen and abusive, who may appear to have taken to drink and drugs are of immediate concern.  Those employees who tend to isolate themselves, no longer socializing should make you wary.  If you spot strange behavior, than report it through the established channels.  Failing to report odd behavior or living in denial is how Penn State found itself the focus of horrid publicity.   Not good.