Fingerprinting is one of the most effective methods in crime scene investigation today. Because every person has a unique fingerprint, identifying crime scene suspects by matching fingerprints from a crime scene to a fingerprint in the Integrated Automatic Fingerprint Identification System (IAFIS) has helped solve many cases. However, fingerprinting technology has come a long way over the past century.

A Brief History of Fingerprinting

Many believe that ancient civilizations were the first to use fingerprinting. Ancient Babylonians pressed their fingerprints into clay tablets to conduct business transactions. The Persians were also known to use fingerprints on official documents. In 1882, Gilbert Thomson of the U.S. Geological Survey used his own fingerprint on a document—the first known use of fingerprinting in the United States. Eventually, governments throughout the Western world began employing fingerprints for criminal identification. In 1903, the New York State Prison system began systematic fingerprinting of criminals. In the same year, the U.S. Army also began fingerprinting enlisted men for identification purposes.

At first, fingerprints had to be examined for a match manually. Matches had to “agree” in 12 different point in order to be considered valid. This was a painstaking and largely subjective process that was often more tedious than it was helpful. However, in 1980, the Federal Bureau of Investigation (FBI) created a computerized Criminal Fingerprint File. The FBI also began regulating the methods of gathering and classifying fingerprints, and created a searchable database which made finding fingerprint matches much easier. Since then, fingerprinting has become a common form of evidence collection and has proved a vital clue in many criminal cases.

New Technologies in Fingerprinting

Historically, forensic scientists have used powders, liquids, or vapors to collect latent (invisible to the naked eye) fingerprints. However, some of these methods can destroy the fingerprint or prevent further analysis.

X-ray detection is the newest and often the most effective form of gathering fingerprints today. A thin beam of X-rays detect salts, sweat, and other residues and makes the fingerprint visible to the investigator on a computer. This method does not require any alteration of the fingerprint, leaving the print intact for further analysis. X-rays can also pick fingerprints up from substances such as wood, leather, or plastic, which traditional methods cannot uncover. An X-ray technique called Micro-X-Ray-Fluroescence can detect other substances and elements present in the print, whereas traditional techniques may uncover only the print itself.

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