USA: Problems with predictive policing
22 August 2016
An analysis of a predictive policing system used by the police in Chicago argues that it does "not significantly reduce the likelihood of being a murder or shooting victim, or being arrested for murder," but it does lead to "increased surveillance" of those listed on the system.
A useful summary is provided by writer Cory Doctorow:
"In Chicago, the "Heat List" system is used to direct policing resources, based on data-mining of social media to identify potential gang-members; the model tells the cops where to go and who to arrest, and is supposed to reduce both violent crime and the likelihood that suspects themselves will be killed -- but peer-reviewed analysis (Scihub mirror) of the program shows that while being on the Heat List increases your chances of being harassed and arrested by Chicago PD, it does not improve crime rates."
In the paper, published in the Journal of Experimental Criminology, Rand Corporation researchers conclude that "once other demographics, criminal history variables, and social network risk have been controlled for using propensity score weighting and doubly-robust regression modeling, being on the SSL did not significantly reduce the likelihood of being a murder or shooting victim, or being arrested for murder" but "individuals on the list were people more likely to be arrested for a shooting regardless of the increased contact."
In other words, predictive policing predicts the police, not the crime. Moreover, as is so often the case, racist training data produces racist predictive models, which allow racist institutions to claim to be undertaking objective and neutral measures while continuing to be totally racist."
See:
Predictive policing predicts police harassment, not crime (Boing Boing, link) and in more detail:
Chicago’s “Heat List” predicts arrests, doesn’t protect people or deter crime (Mathbabe, link)
Only the abstract of the article in question is freely publicly available:
Predictions put into practice: a quasi-experimental evaluation of Chicago’s predictive policing pilot (SpringerLink, pdf)
Police in the UK and elsewhere in Europe have in recent years begun to make increasing use of "predictive policing" systems. Can we expect to see scientific analyses of the their effectiveness?
Background:
Predictive policing: mapping the future of policing? (openSecurity, link)