essity of the use of physical force. Police seek and preserve public favour not by catering to public opinion but by constantly demonstrating absolute impartial service to the law. Police use physical force to the extent necessary to secure observance of the law or to restore order only when the exercise of persuasion, advice and warning is found to be insufficient. Police, at all times, should maintain a relationship with the public that gives reality to the historic tradition that the police are the public and the public are the police; the police being only members of the public who are paid to give full-time attention to duties which are incumbent on every citizen in the interests of community welfare and existence. Police should always direct their action strictly towards their functions and never appear to usurp the powers of the judiciary. The test of police efficiency is the absence of crime and disorder, not the visible evidence of police action in dealing with it.Although the objective was on crime prevention, the focus eventually turned to investigation and apprehension of criminals. Therefore, the need for private police was still great.Allen Pinkerton was one of the developers of the railroad police, as well as contract security forces. He was appointed the deputy sheriff of Cook County, and in 1843, Chicago’s first detective. Pinkerton later resigned his position due to economic pressure. He then started the Pinkerton National Detective agency, and focused on apprehending railroad criminals, and setting up security systems for railroads. During the Civil War, Pinkerton was called on by President Lincoln to establish a secret service department, where he did intelligence work for the Union Army. In the 1860’s and 70’s Pinkerton’s agency received National attention by apprehending train robbers and bandits. Currently Pinkerton Inc. is the largest private se...