Letter: No one cause for mass murder

Susan Hancock's "Why violent death stalks the shores of paradise" (9 February) on why New Zealand has had five mass murders since 1990, shows the perils of instant analysis. Ms Hancock talks of the possibility that the killers were "marginalised" by unemployment or mental illness, but one was retired, another a student with a part-time job, and two were regularly employed. Only two suffered from mental illness. All but one of the multiple murders have been domestic. Their causes will be found in particular circumstances, not sociological generalisations.

Bruce Rennie

Christchurch, New Zealand