Zero tolerance policing is enormously expensive  The enormous expense of zero tolerance in money and manpower and prisons actually makes policing worse. Either we have to throw limitless money at doubling the number of officers (it is almost impossible to recruit and train so many even if we could afford it). Or we have to divert officers away from investigations and serious crime prevention in order to put them back on the pavement. This reduces detection of important crimes in return for catching graffiti artists. Even when reported crime rates drop this does not prove that zero tolerance achieves anything because it is corporate crime, large scale drug dealing that is ignored and these are rarely reported. [1]  [1] Croall, Hazel, Understanding white collar crime, Open University Press 2001, www.mcgraw-hill.co.uk/openup/chapters/0335204279.pdf , accessed 21 September 2011