Murder-suicide in New Hampshire, 1995-2000.

Combined murder-suicide is defined as homicide(s) followed by the perpetrator's suicide within 1 week of the homicide(s). This phenomenon is observed worldwide with generally similar incidence rates. The authors report data from New Hampshire, a population distinguished from those in previous United States studies by its location, racial homogeneity, nonurban character, and low homicide rate. Sixteen murder-suicide events occurred in New Hampshire between October 1995 and October 2000. This represents an incidence of 0.26 per 100000 person-years, a rate similar to previously reported values. Murder-suicide events accounted for 14.7% of all homicides in the state, higher than previous studies but not unexpected in view of the state's lower homicide rate. Most perpetrators were male (94%), and most victims were female (88%), often in a spousal or consortial relationship. Firearms accounted for the majority of deaths. Various cofactors are examined, and a comparison of two recently proposed classification systems is discussed.