LETTER: Crunching some deadly numbers

“Dinner Party Intel — Cape of Crime” (Fox, February 22-28) refers.

The FM states that “the latest police statistics show the [Cape Town] CBD is the worst place for violent crime in South Africa: 3,769 incidents between October and December — a 22.1% rise from the same period in 2022”. 

This is an incorrect interpretation of the data.

The 3,769 incidents are the “17 community-reported crimes” recorded by the police, including offences such as shoplifting, theft and commercial crime. These are not violent offences. Cape Town central (“the CBD”) recorded zero murders and 953 violent crimes — a quarter of the total incidents. 

By way of comparison, Joburg central recorded 1,105 violent crimes including 44 murders, while Durban central recorded 1,016 violent crimes including 20 murders.

The relative reported violent crime rates of these CBDs are unclear, as population inflows to CBDs fluctuate and are difficult to estimate.

Population is of course necessary to calculate rates of crime for legitimate comparison. In a further misinterpretation, the FM goes on to say that “five districts — Mfuleni, Gugulethu, Nyanga, Khayelitsha and Delft — have the highest murder rates, except for Inanda in eThekwini”.

The police figures referred to are murder counts, not murder rates. The five areas mentioned do indeed have the highest count of murders, but this is primarily because these areas cover vast populations. Inanda covers an estimated 356,000 people compared with an average police station area of only 50,000 people. 

Population size is key. Nyanga eventually dropped out of its perennial top spot in the so-called murder top 30 only because Samora Machel was created out of the Nyanga area, which removed about 75,000 people (and their associated murder count). Summing Nyanga and Samora Machel results in a murder count of 106; Nyanga would still occupy the top spot if its borders had remained the same.

However, this doesn’t mean Nyanga has the highest murder rate. The old Nyanga borders contained a population of just more than 250,000, making the quarterly murder rate 42 per 100,000. Though this is a very high rate, it is not the highest. Jeppe in the Joburg metro area, with an estimated population of only 84,000, recorded 66 murders, making its quarterly murder rate 79 per 100,000, almost twice the rate of Nyanga.

Finally, when interpreting crime data, crimes reported to the police by the community cannot be taken as a reflection of the true crime incidence or even relative crime trends, as reporting varies over time and place. Low trust and poor policing reduce reporting.

Unfortunately the police service itself has tended to rely on total reported crime to allocate resources, which has led to absurdities such as very high murder rate areas (with low trust and low reporting) having very low rates of policing. Police minister Bheki Cele signalled in his presentation that the police will rely more on murder rates in future allocations, but it remains to be seen if this actually occurs.

Jean Redpath
Senior researcher, Dullah Omar Institute, University of the Western Cape

The FM welcomes concise letters from readers. They can be sent to fmmail@fm.co.za