Undercover Agents of the Berlin Police (1913) The great metropolis of Berlin had one of the largest police forces in Germany. The police spied on Socialists and other “enemies of the state,” and had undercover agents to infiltrate criminal organizations. This 1913 photograph shows members of Berlin's police force disguised as hoodlums and vagabonds. Two officers in the front row (third from the left, seated, and fourth from the right, seated) are dressed as women.