A study carried out by A. Harriott shows that the homicide rate in Jamaica is four times higher than the world rate, with the city of Kingston having the highest rate in the world at 109/100,000, followed by Washington D.C., at 67/100,000. According to this researcher, there is a direct relationship between the rate of murder and the rates of other violent crimes-robberies, rapes, etc. In Jamaica, historically, most murders were crimes of passion. In 1963, in 64% of the murder cases, the victims were known to the offender, and domestic violence accounted for 28% of all homicides, while in 1993, this declined to 16%. This does not mean that cases of domestic violence are on the decline, it means that the murder rate - especially since the increase in the number of illegal guns on the island - is going up."