When and why where fingerprints first used in the US?

Fingerprints were first used in the United States in 1892 by the Chicago Police Department. However, it wasn't until the early 20th century that fingerprints became a widely used method of identification in the US. In 1903, the New York State Bureau of Criminal Identification was established, which was the first state-wide fingerprint repository. In 1924, the Federal Bureau of Investigation (FBI) established a national fingerprint repository. By the 1930s, fingerprints were being used by law enforcement agencies across the country.

The use of fingerprints as a method of identification was based on the fact that each person's fingerprints are unique and do not change over time. This makes fingerprints an ideal way to identify individuals, even if they are wearing disguises or trying to conceal their identities.

Fingerprints are created by the ridges and valleys on the skin of the fingers. These ridges and valleys are formed by the way the skin is folded during embryonic development. The pattern of ridges and valleys is unique to each individual and remains unchanged throughout life, even if the size or shape of the fingers changes.

The use of fingerprints has revolutionized the field of criminal investigation and has helped to solve countless crimes. It is a powerful tool that is still used today by law enforcement agencies around the world.