The United States Secret Service was born to thwart counterfeiting in 1865. Shortly afterwards in 1903, President McKinley was assassinated. The Secret Service was bestowed the responsibility of permanent presidential protection.
In 1908, U.S. Attorney General Charles Bonaparte under president Theodore Roosevelt, created an organization that would handles nothing but federal investigations, amply named Federal Bureau of Investigation, better known as the FBI.
In an attempt to enforce Prohibition the Bureau of Internal Revenue was implemented in 1920. The FBI expanded it’s services to include a crime laboratory and made the agency available to state and local agencies in 1932. A few years later in 1935, FBI stared the National Academy that offered training courses to state and local police. In 1967, the FBI created the National Crime Information Center, or NCIC.
The Drug Enforcement Administration or DEA began its service to the U.S. in 1973.
photo by https://www.secretservice.gov/about/history/150-years