Policing

Major steps toward professionalism were led by a number of prominent police chiefs around the nation including Vollmer. Police departments adopted codes of ethics to combat corruption and established education requirements for recruits. Police academies were established and San Jose State College offered the first training program for professional policing in 1931. Police departments adopted formal rules and hiring practices to further separate themselves from political influence.

Police departments also adopted modern technologies such as establishing forensic laboratories. The biggest technological change had come by the 1920s with the automobile. Policing was revolutionized with the widespread use of police cars and two-way radios. The radios put officers in continuous contact with their sergeants at the police station and allowed them to be much more responsive to calls from the public. Unfortunately, patrol cars also served to separate police from the community as they were no longer on foot patrols. Nonetheless police were more efficient, responded faster, and had new technologies to help them solve and prevent crimes. These tools led to greater professionalism and a drop in corruption.

During this time J. Edgar Hoover (1895–1972) overhauled the U.S. Bureau of Investigation into a top notch professional federal police agency. Hoover and his G-Men, as the agents were called, became famous with their capture and killing of several notorious crime figures in the early 1930s. As a result Congress gave the bureau expanded crime fighting responsibilities such as kidnappings, crossing state lines to avoid prosecution or testifying, carrying stolen goods across state lines, and drug enforcement. In 1935 the agency changed its name to the Federal Bureau of Investigation (FBI) and established an academy to train local police officers.

Like other federal agencies, the FBI grew throughout the 1930s with its new responsibilities—which in turn led to a decline in the role of U.S. marshals. Marshals, however, continued to serve court papers and to patrol the courts. The federal government had also expanded its policing powers with the addition of the Immigration and Naturalization Service (INS) in 1940 as part of the Department of Justice.

The Texas Rangers had existed off and on through the 1800s and were officially established in 1874. (© Underwood & Underwood/Corbis)