How our immune systems could help us understand crime

Taxation and death may be inevitable but what about crime? It is ubiquitous and seems to have been around for as long as human beings themselves. A disease we cannot shake. However, therein lies an idea, one that Oxford Mathematician Soumya Banerjee and colleagues have used as the basis for understanding and quantifying crime.

Their starting-point is that crime is analogous to a pathogenic infection and the police response to it is similar to an immune response. Moreover, the biological immune system is also engaged in an arms race with pathogens. These analogies enable an immune system inspired theory of crime and violence in human societies, especially in large agglomerations like cities.

An immune system inspired theory of crime can provide a new perspective on the dynamics of violence in societies. The competitive dynamics between police and criminals has similarities to how the immune system is involved in the arms race with invading pathogens. Cities have properties similar to biological organisms - the police and military forces would be the immune system that protects against invading internal and external forces.

Police are activated by crime just like immune system cells are activated by specialized cells called dendritic cells. Non-criminals are turned to criminals in the presence of crime. Hence crime is like a virus. This specifically simulates a spread of disorder.  Police also remove criminals similar to how T-cells kill and remove infected cells.

The work has implications for public policy, ranging from how much financial resource to invest in crime fighting, to optimal policing strategies, pre-placement of police, and the number of police to be allocated to different cities. The research can also be applied to other forms of violence in human societies (like terrorism) and violence in other primate societies and social insects such as ants. Although still an extremely ambitious goal, in the era of big data we may be able to predict behaviours of large ensembles of people without being able predict actions of individuals.

The researchers hope that will this be the first step towards a quantitative theory of violence and conflict in human societies, one that contributes further to the pressing debate about how to design smarter and more efficient cities that can scale and be sustainable despite population increase - a debate that mathematicians, especially in Oxford, are fully engaged in.

For a fuller explanation of the theory and a more detailed demonstration of the mathematics click here and here for PDF.