The Gestapo and German Society

How were the Gestapo able to detect the smallest signs of non-compliance with Nazi doctrines, and how could they enforce their racial policies with such ease? Robert Gellately argues, controversially, that there was a three-way interaction between the Gestapo, the German people, and the implementation of policy; the key factor being the willingness of German citizens to provide the authorities with information about suspected `criminality'.