Ever since we realized that catching a malefactor wasn't as simple as throwing them in the water to see if they floated, we had to turn to science. And over the years, there have been some homicide cases that really changed things. Here are ten people whose killings paved the way to a new era in crime-solving.
Gabrielle Bompard and Michael Eyraud were not a pleasant pair even before they murdered Toussaint-Augustin Gouffé, and they only became less pleasant from there on in. By the time their protracted murder case got to court in the 1890s, everyone knew that Bompard had lured Gouffé to her rooms, Eyraud had hid behind a curtain and slipped a noose around Gouffé's neck, and they had both stuffed the body into a trunk and thrown the trunk in a ravine. What wasn't established was how much Eyraud, a hypnotist, had bent Bompard to his will.
The formal terminology used in the investigation and trial was hypnotism and mesmerism. What the experts who were called in to advise and testify seemed to be debating was what we, today, would call "diminished responsibility." To what extent was Bompard, younger, poorer, physically abused, able to resist her lover? Instead of calling in lay people to provide testimony about evil influences, or Bompard's character, law enforcement officials called in practitioners of the nascent science of psychology and neurology (one of the expert witnesses was Freud's teacher) to give scientific evidence about the psychological underpinnings of the human mind. It seemed to work. Both were convicted, but only Eyraud was executed.
During the early 1800s, court officials were not yet up to examining people's minds. They were still working out the details of how to treat people's bodies. The process was complicated by the fact that those bodies were not kept in the best shape. Some were actually buried and had to be exhumed before forensic experts could examine them. One man, a Spanish scientist turned expert witness in Paris, earned a bad reputation for himself among prosecutors. Mathieu Orfila determined that, in cases when the victim had been buried for some time, the body might become contaminated with arsenic from the ground. The accused might then be executed for the death of a "victim" who had actually died of natural causes.
His philosophy came back to bite him in the 1830s, when he was called in to argue for the prosecution in the case of a man who was accused of poisoning his own son. The body had been exhumed, and tested positive for arsenic. The defense was insisting that it came from the ground in which the body was buried. Orfila fought back, first doing tests on exactly how a body in the ground picks up arsenic, and then testing the ground around where that particular body had been buried for traces of arsenic. He proved that, although a body might absorb arsenic from the ground, this one hadn't. The man was convicted, and from then on, those who exhumed bodies collected soil samples as well.
Back before photography was feasible, and before anyone really thought about preserving a crime scene, Hans Gross was an "examining magistrate" in Austria. One day, in the mid-1800s, he was called in to deal with a suicide. A gravely ill man had ended his life by hanging himself from one of the beams in the ceiling of his house. Gross took out a sketch pad and quickly sketched the scene before taking the body down.
It was only later, looking at his sketch, that he realized that the body was hanging in the middle of the room and there was no chair, no table, no possible way for the a sick man to have climbed up to the ceiling and hanged himself. It was not a suicide. In one of the few relatively innocent outcomes in forensic science history, the death wasn't technically a murder. Gross brought in the two servants in the house for questioning. They confessed that they had left the old man to fend for himself for an evening, and by the time they came home he was dead. They had faked a suicide to avoid the stigma of having abandoned an invalid. They didn't realize that by doing it they would look like murderers. Gross later founded an institute of "criminalistics" at a nearby law school, and standardized the technique for photographing, and otherwise preserving, every crime scene.
Gross wasn't the only person trying to apply a scientific system to criminal investigation. Perhaps the best known investigator of the 1800s was Alphonse Bertillon. He, like Gross, insisted on photographing crime scenes, and eventually came up with an orderly way to grid out a crime scene, so the scene could be reconstructed. He also came up with the "Bertillon System," a complicated set of measurements that involved measuring everything on a criminal, from the arm span to the length of the ear. The problem was, the Bertillon System was tough to teach, required dozens of measurements, each of which could be screwed up, and even accurate measurements would change as a person aged.
When fingerprints as an investigation system came into fashion, Bertillon hated the very idea of them. Then, in 1903, the penitentiary in Leavenworth housed two Will Wests, and two cards that identified Will West as a murderer. They were, according to their Bertillon measurements, identical. They had the same name. One claimed not to be the man listed on either of the Will West cards, and insisted that he was not meant to be incarcerated. The prison simply had a double card for William West. Fingerprinting was coming into fashion, despite Bertillon's efforts, and each card for Will West included the prints of the convicted man. By using the fingerprints, investigators were able to match each Will West to his card and to his murder. The case of the "West Brothers" was the beginning of the end for the Bertillon System and the solidification of the fingerprint system.
This was remarkable progress, as the first fingerprint conviction had happened only ten years before the "West Brothers." Juan Vucetich was born in Croatia, but lived and worked in Argentina. He was a police official who studied the latest methods in criminology, including the very new idea of using fingerprints at the crime scene as evidence. Soon he had a chance to put the science into practice with a very nasty case.
Francisca Rojas shocked Buenos Aires when she was found one day by the bodies of her two young sons. She had a nasty, but non-fatal, gash on her throat. She insisted that an intruder had killed her sons and attacked her. Vucetich carefully examined the scene and found a bloody fingerprint belonging to the attacker on the door post to the house. When he checked Rojas' fingerprints, they matched those of the "attacker." Rojas was the first person to be convicted using fingerprints as evidence.
John Bodle got Marie Lafarge sentenced to death. He didn't inform on her. He didn't prosecute her. He didn't even know her. He just pissed off a very important guy. Bodle killed his father in order to get his inheritance. We know this because, shortly after he was acquitted, Bodle bragged about committing the crime. He was acquitted because John Marsh, the chemist who was in charge of proving the use of poison, showed up in court empty-handed.
This was through no fault of Marsh's. The test for arsenic, at that time, produced a results that faded away over time, so a jury had to take the chemist's word for it. Marsh, upon hearing about Bodle's admission, went to work and came up with a test for arsenic that produced enduring results. Although record-keeping was standard in criminal courts since the 1400s (and in many places well before that) this began a strong shift towards keeping enduring proofs of all evidence, including chemical evidence. Lafarge's trial was the trial at which the Marsh test debuted. The prosecutors used the test when they had the body of Lafarge's husband, poisoned just after drinking eggnog, tested. They found nothing. They found a lot of arsenic in the eggnog, though. Our old friend Orfila testified at trial, the Marsh test was waved around, and Lafarge was convicted. She was a figure of sympathy in her time, wrote her memoires in jail, and some still believe she was innocent.
On February 14, 1929, five members of George "Bugs" Moran's gang tried to hijack a whiskey shipment meant for Al Capone. When they got to the garage where the shipment was meant to arrive, four strange men walked up to them. Two of the men, in police uniforms, ordered the Moran gang up against a wall. When the gang lined up, the strange men opened fire. One used a twelve-gauge shotgun, and two others used Thompson submachine guns.
Very little of this was known just after the crime. Although one gang member survived for a few hours, he wouldn't talk. The St Valentine's Day Massacre, as it came to be called, left no survivors and no direct witnesses, although some suspected the police were involved. In came Dr Calvin Hooker Goddard, a scientist who had first started intensively researching guns during his time in the army in World War I. He came to realize that the grooves on bullets were like fingerprints for guns. He could identify the model of the gun from the evidence left at the scene. In the case of the massacre, he started by ruling out any actual police-issue guns being used in the massacre, clearing the police force. He even proved he could identify the individual guns used. When Fred Burke was arrested for the shooting of a police officer, and two Thompson submachine guns were found at his house, Goddard identified them as the guns used to carry out the massacre. He became the person to prove, to science and to the public, that crimes could be tracked by guns and not just people.
Look at popular forensics books and there is one case that usually gets mentioned. John Toms, in 1784, killed Edward Culshaw with a pistol shot to the head. There's no real information on why John Toms did this. There's just a blurb, saying that Toms had a bit of torn newspaper in his pocket. Culshaw carried the matching torn piece in his head. At the time people used spare scraps of paper to secure the gunpowder and pellet together. The fact that Toms had the matching piece of paper established him as the murderer. This was, it seems, the very first time forensic science was ever used.
Think about it from Toms' perspective. The very first time such a science is ever used in the history of the human race, and you're the one that gets caught. You would just kick yourself, wouldn't you?
Here's a murder case that went all the way to the Supreme Court. In November of 1920, Dr. Robert Brown was shot to death in his office. A young man running from the office was chased by Brown's colleague. The young man fired a few shots at the colleague, but missed him. Some time later, a young man who had been arrested for burglary confessed to the murder. How the confession was obtained is still a matter of controversy. By the time the case went to trial, the young man, James Frye, had retracted his confession and claimed he was visiting a friend at the time of the murder. His attorney had him undergo a new kind of test - administered by William Marston. (Yes. That one.)
According to the Marston, the "lie detector test" proved that Frye was innocent, but the judge presiding over the case threw the results of the test out and Frye was convicted. Frye's lawyer appealed, saying that Marston's test was scientifically valid and the judge should not have thrown it out. The Frye case finally made it to the Supreme Court. The justices sided with the judge. The Frye case, then, set the standard that, for many states, still dictates what can and cannot be considered expert scientific testimony and evidence.
Just when a scientific principle or discovery crosses the line between the experimental and demonstrative stages is difficult to define. Somewhere in this twilight zone the evidential force of the principle must be reorganized, and while courts will go a long way in admitting expert testimony deduced from a well recognized scientific principle or discovery, the thing from which the deduction is made must be sufficiently established to have general acceptance in the particular field in which it belongs.
The Salem witch trials are not famous for their application of scientific evidence, but they did put one mark in the "win" column for science. The trials were seen as something of a miscarriage of justice even during their own time. The villagers of Salem were famous for being a nasty bunch who feuded with each other and cheated everyone else. When word got out that they were using "spectral evidence" in court, the people in the surrounding countryside rolled their eyes. The term spectral evidence is literal. The accusers saw specters of the accused, often right in the court room, and their testimony about the actions of these phantoms was used as evidence. The eye-rolling stopped when people like Sarah Goode and John Proctor were executed because a gang of teenage girls kept insisting that they were pinching them and strangling them in open court. The committee gathered together to address witchcraft was essentially murdering people to stop their "spirits".
There was a lot of debate over whether this should be used as evidence, even in Salem itself. But no one put a stop to it - not even the royally-appointed governor of the Province of Massachusetts Bay, William Phips. Then someone accused William Phips' wife of being one of the witches. Things started changing fast. Not all of the accusations were brought to court anymore. The trials were beginning to be shut down. And, within months, Governor Phips put an end to the practice of using spectral evidence in court. He deemed it flimsy, and not scientific.
Adelaide and Edwin Bartlett did not have a particularly happy marriage. She was in love with a local pastor. He was convinced that he had syphilis and used massive doses of mercury to treat it. They no longer shared a bed, but they slept in the same room. It was not exactly a surprise when, one morning in 1886, Edwin was dead. What was surprising was the fact that he was dead due to a massive dose of chloroform. Chloroform is well-known for evaporating quickly. What's more, the chloroform was entirely in his stomach, not in his lungs as is the usual case when someone is forced to ingest chloroform. Chloroform was not, however, on his bank statement. Adelaide had gotten the pastor to buy her the poison.
Adelaide not only admitted that she sent the man she loved to get the stuff that poisoned her husband, she said she regularly administered it to her husband. His disease made him go mad with desire, she claimed, and she dosed him with chloroform to defend herself. She maintained, though, that she hadn't dosed him that night. Adelaide said that Edwin was a hypochondriac, and took whatever medicine he could get his hands on. He probably had just opened the bottle of chloroform in the night and drunk it. This seemed unlikely. Chloroform has a heavy smell and an unpleasant taste, both of which would have been familiar to Edwin. He wouldn't have drunk it - but then again, the much smaller Adelaide couldn't have forced him to drink so much or done it so neatly. In the end, the jury found her not guilty, but only after making a speech during which they informed her that they thought she was probably guilty. The case was of such interest to the budding science of forensics that, after her acquittal, the head of a local hospital said, "Now that she has been acquitted for murder and cannot be tried again, she should tell us in the interest of science how she did it."
[Via The Little Demon in the City of Light, The Chemist, How Science Tracks the Criminal, The History of Fingerprints, Dr Calvin Hooker Goddard, The Polygraph and the Frye Case, Careers in Forensic Science, The Salem Times, Adelaide Bartlett and the Pimlico Mystery]