The science of policing

Dr. Henry Faulds noticed the patterns that human fingertips had left behind on some old pottery samples and recognized their value as identifiers. Faulds also developed a method for classifying fingerprints, but it wasn't until the 1890s that an Argentine police officer named Juan Vucetich launched the first fingerprint files (and not incidentally also made the first successful fingerprint comparison in a criminal case). Although not a scientist, Vucetich's visionary understanding of the significance of fingerprint identification was a giant leap forward in the science of identification of both criminals and ultimately, their victims.

Meanwhile, English anthropologist Sir Francis Galton, who had long studied fingerprints as a method of identification, devised the first known system for classifying them. Another of Galton's observations, that fingerprints are unique to the individual, added to their criminal justice value. In 1902 Dr. Henry Depelouze DeForrest, a surgeon with the NYPD and eventually, also the city's chief medical examiner, officially introduced the science of fingerprint identification in criminal cases to U.S. agencies. DeForrest subsequently invented a device called the dactyloscope, which recorded fingerprint patterns. Today, of course, fingerprint identification remains at U.S. law enforcement's fingertips through the digital Integrated Automated Fingerprint Identification System, maintained by the Federal Bureau of Investigation.

Reaching into evil minds

Jack the Ripper wasn't simply one of history's most notorious serial killers; his London rampage also helped jumpstart the art of criminal profiling. Physicians Thomas Bond and George Phillips analyzed the remains of the murderer's victims, as well as the crime scenes from which the bodies of the victims were recovered, and made some rough guesses as to the type of individual who might have committed the infamous Whitechapel slayings. Since the Ripper has never been conclusively identified, no one really knows how on-the-mark the two doctors were, but the art of criminal profiling—like the crimes of Jack the Ripper—have continued to fascinate both the public and law enforcement professionals.

The case that turned behavioral analysis into a true law enforcement tool was probably also one of the most vexing for the NYPD. The so-called "Mad Bomber," George Metesky, planted numerous bombs in the city, targeting landmarks such as Grand Central Station, but Metesky's first target was Consolidated Edison, the city's electric provider.

After 16 years of tracking the bomber with no luck, police turned to the New York State Assistant Commissioner of Mental Hygiene, a psychiatrist named James Brussel. Brussel studied notes and other documents connected with the case and produced a profile of the bomber. When police apprehended Metesky, Brussel's detailed profile was right on the money.

The FBI took an early interest in tying crimes to personalities and created its Behavioral Sciences Unit in 1974, but psychological professionals have sometimes differed with their approach. Since its initial inception, the unit has now added individuals with psychiatric and psychological backgrounds to the mix. Among the field's contemporary luminaries: Dr. C. Gabrielle Salfati, a pioneer in investigative psychology, and Dr. Anthony Pinizzotto, who is both a forensic psychologist at the FBI's Behavioral Science Unit and a Catholic priest.

The language of the dead

When it comes to working a homicide, there is no better partner than a good forensic pathologist. It's a science that has been hundreds of years in the perfecting, with an interesting and sometimes contentious history.

Autopsies were forbidden in many early cultures, including that of most of ancient Greece. However, one Greek physician, Herophilus (born in 335 BC) is believed to have been the first to conduct autopsies—at least in ancient Greece. Other Greek and Roman physicians after him also practiced autopsy, but the science was generally banned in Europe during the Middle Ages. On the other side of the globe, Chinese physicians practiced medicolegal investigation beginning in the Song Dynasty (960-1279).

Scholars say that European medicolegal autopsies date from 1302, when they were performed in Bologna, Italy. Executed criminals reportedly acted as the unwilling stars of these surgical events. And although many physicians in both the West and East added to the body of knowledge of medicolegal investigations, one scientist was considered the first modern pioneer of the field: Dr. Alexandre Lacassagne (1843-1924) a French doctor, professor and criminologist who authored, "The Principles and Practice of Medical Jurisprudence."