A positive relationship between ambient temperature and violent crime has been reported internationally in a number of studies. This finding has led some authors to suggest that climate change could lead to an increase in the frequency of violent crime. This presentation uses a Bayesian regression model to assess whether a relationship between temperature and violent crime is present in Auckland, New Zealand, using data obtained from the NZ Police and NIWA. In the period July 1996 to July 2009, the daily rate of recorded assaults was positively related to daily maximum air temperature in central Auckland, with an approximately 2% increase in recorded assaults for each 1°C increase in temperature. This relationship held when controlling for population size, month, day of week, public holidays, trend, and solar radiation. However, there are several factors that limit psychologists’ capacity to use findings such as these to generate quantitative forecasts predicting how climate change may affect violent crime in the future. These factors include the wide range of influences on violent crime (including factors both related to and not related to climate change), a lack of understanding of the causal mechanisms underlying recent trends in violent crime, and the novelty of climate change as a problem for human society. This presentation will comment on how these problems exemplify several challenges that make the generation of accurate predictions relating to how climate change may affect human behaviour a particularly difficult task.