Two personality disorders appear to be linked to many incidents of workplace violence and, in particular, to homicide perpetrated by a lethal employee

or ex-employee. These are antisocial personality disorder and borderline personality disorder.

DSM IV (Diagnostic and Statistical Manual of Mental Disorders) provides indicators of behavior which are often associated with these disorders:

Indicators for Antisocial Personality Disorder

Disregard for the rights of others

Violation of the rights of others

Persistent non-conformance to laws, regulations and social norms

Deceitfulness and lying

Impulsive and erratic behavior

Irritability and aggressiveness

Reckless disregard for the safety of others

Consistent irresponsibility (domestic and at work)

Lack of remorse for harmful actions to others

Indifference to others

More prevalent in males than females

Often associated with inferior socioeconomic condition

More prevalent in urban settings

Indicators for Borderline Personality Disorder

Significant fear of real or imagined abandonment

Pattern of unstable interpersonal relationships

Unstable sense of self or self-identity

Impulsive, self-damaging behavior

Suicidal behavior

Behavior threatening to self or others

Unstable moods and reactions

Chronic feelings of emptiness

Inappropriate and intense outbursts of anger

Fighting and other forms of physical aggression

Paranoid ideation or severe dissociative symptoms

More prevalent in females than males

Also associated with violent behavior is the presence of a psychosis which can be associated with a variety of psychological disorders. DSM IV

provides these general indicators of psychosis:

General Indicators of Psychosis

Delusions or hallucinations which are bizarre and may be auditory

Persistent inability to function effectively in a social or work setting

Disorganized or incoherent behavior or speech

Significant paranoia accompanied by delusional thinking

Unusual physical or motor activity

Extreme and persistent negativism or fear

Incoherent and inappropriate communication with others

Disorganized or incoherent thought process

Finally, a major depressive episode can lead to violent behavior. Although the violence resulting from this disorder is usually self-directed, it can be

directed towards others:

Indicators of a Major Depressive Episode

Feelings of sadness, emptiness or worthlessness

Diminished interest in normal activities

Significant change in weight and/or appetite

Insomnia or hypersomnia

Psychomotor agitation or retardation

Reduction in normal levels of efficiency

Fatigue or loss of energy

Inappropriate feelings of guilt

Sorrowful, tearful appearance

Deterioration of physical appearance

Increased irritability and frustration

Reduced ability to concentrate and/or indecisiveness

Recurrent thoughts of death or suicide