In South Africa, as in the USA, gun control is a subject of much public interest and debate. In a project intended to study the apparently increasing tendency for violent crime to involve firearms, Dr L. B. Lerer collected data relating to homicides and suicides from the South African Police mortuary in Salt River, Cape Town. The data consist of all the homicide and suicide cases appearing in the deaths registers relating to the 6-year period from 1 January 1986 to 31 December 1991. One question of interest that was examined by means of hidden Markov models was whether there is an upward trend in the proportion of all the deaths recorded that are firearm homicides. A question of interest that arises from the apparently increased proportion of firearm homicides is whether there is any similar tendency in respect of suicides.