The History of Forensic Science: Identifying Jack the Ripper

From the Lecture Series: Forensic History — Crimes, Frauds, and Scandals

By Elizabeth A. Murray, PhD, Mount St. Joseph University

The murder spree of Jack the Ripper—the first widely reported “serial killer”—was a grisly chapter in the history of forensic science. Methods developed in the pursuit of this killer are still used today.

Jack the Ripper in action
(Image:  guidopiano/Shutterstock)

A Media Sensation: Jack the Ripper

The landmark case for crime reporting created the first known major media crime sensation, which started locally, then spread across much of the world. It’s a forensic analysis that began in the late 1880s and is still ongoing today.

This case has spawned hundreds of theories, countless publications, and has had some of forensic science’s greatest minds re-examine it. But, despite all this effort, the identity of the perpetrator is still unknown. He goes by the legendary name of Jack the Ripper.

Although the exact number of victims is not known, most authorities agree that five women killed between August 31 and November 9 of 1888 in the East London area known as Whitechapel are confidently the work of one serial killer.

This is a transcript from the video series Forensic History: Crimes, Frauds, and Scandals . Watch it now, on Wondrium.

Many sources also attribute a sixth victim from earlier that August to Jack the Ripper. Some theories raise the number of victims to 11 women, and still, other sources go higher, perhaps including a 7-year-old boy, encompassing a larger group of attacks that took place in the same general vicinity between February 25 and December 29 of 1888.

But the earlier assaults during this broader 10-month period seem more haphazard, and the victims were not killed. As a result, most scholars believe those are not connected, but rather, just reflect the impoverished, dangerous, and crime-ridden East End of London at the time. It’s also possible, though, that at least some of those earlier attacks were the clumsier beginnings of a killing spree that Jack the Ripper ultimately mastered

How Were the Ripper Crimes Connected?

In addition to time, what other evidence has been used to connect some of these crimes and the victims of Jack the Ripper? The reason most agree five female victims are definitively linked, and why some authorities insist others are decidedly not the work of the same killer, is what forensic scientists call modus operandi, or simply the perpetrator’s MO. These five women were prostitutes who lived and worked in the slums of the East End of London.

Learn more about the continuous interplay between forensic advances and larger societal changes

Part of the Ripper’s MO was to prey upon women of the night, the time when these killings occurred. But no semen was discovered in any of these cases, which not only further links them, but also suggests that rape was not part of the MO. The murders are further connected by increasing brutality, showing an escalation of sorts as time went on, a phenomenon seen in the careers of many criminals.

Investigators look at these same facets today when they suspect crimes might be linked—victim choice, the weapon used, level of brutality, escalation. Connecting similarities like these are, in a way, just common sense. Much of forensic science analysis, at least within the mind of the investigator, is what our brains do every day in countless situations: Compare data and recognize patterns. As an example, let’s look at the evidence used to connect the Whitechapel casualties in 1888.

Map showing the sites of the first seven Whitechapel murders committed by Jack The Ripper
The sites of the first seven Whitechapel murders committed by Jack The Ripper. (Image: By Ordnance Survey; modified by User:ΑΩ – 1894Public domain)

Eyewitnesses in the Jack the Ripper Cases

Eyewitnesses are, without fail, a big lead for investigators, right? Not always. In this case, numerous people were willing to say they saw a couple in the area that evening, or at least saw Elizabeth Stride, victim three, with a man in the area between around 11:00 pm and 12:45 am on the same night she was murdered. But few of them could agree on the appearance of the man they claim to have seen or the clothing he was wearing.

Image of the Illustrated Police News, 6 October 1888.
Discovery of Elizabeth Stride’s body seen by 
The Illustrated Police News , October 6, 1888. (Image: By Unknown/Public domain)

One witness told police the couple was kissing in the recessed doorway of a building and that he heard the man say to Stride, “You would say anything, but your prayers.” Another witness who claimed to have seen Stride about 12:30 am was a young police constable who said the man with her carried a package about 18 inches long, wrapped in newspaper. Eyewitness testimony can be notoriously unreliable, including the well-known phenomenon of people falsely reporting events to get attention or to jump on the media-frenzy bandwagon around incidents like this.

But one eyewitness said he saw Stride at 12:45 am in the same location where her body was found in an altercation with a man. The witness said the man had dark hair, a thin mustache, was about 5′ 5″ tall, broad-shouldered, and around 30 years old.

This was consistent with the description of the man made by the police constable. The onlooker thought he was watching a domestic argument, and he didn’t want to get involved. Especially after the attacker took notice of the witness, so the bystander decided to keep moving.

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We’ve all heard of cases in the news in which people don’t want to get involved, or maybe they only realize the gravity of what they saw after they hear later that they witnessed a crime. The discovery of Elizabeth’s body, just 15 minutes after this man saw what he thought was a domestic dispute, suggests that the witness, who was a Hungarian Jew and had to be interviewed through an interpreter, may not have only seen Jack the Ripper, but stumbled upon him in the process of killing one of his victims.

Authorities took the account of this Hungarian quite seriously for two main reasons. First, the witness came forward despite significant anti-Semitic tensions in the area. Second, he saw what he described as an altercation, including the woman’s very low-pitched cry, before the attacker noticed the bystander, causing the Hungarian to rush off.

Investigators already believed that the Ripper’s MO was to strangle or slit his victim’s throats, cutting them twice, so deeply that their airway was cut, disabling them from screaming during the rest of the attack. Police theorized that the Hungarian may have stumbled upon the attacker as he was just beginning to execute his typical MO on Stride. But once the Ripper realized someone was watching, he ran off after only a single cut to the victim’s neck, abandoning the rest of his standard mutilation.

Early Forensic Mistakes on Jack the Ripper Victims

Another unusual aspect showed up with the Eddowes case, victim four: A message, neatly written in chalk on the wall in the busy marketplace, right next to where a piece of her apron had been discarded. It said, “The Juwes [sic] are the men that will not be blamed for nothing.” The meaning of this message is still open to debate and interpretation, but it echoed the anti-Semitism that was dividing the community about the murders.

Terror in society often stirs up wild emotions, including the desire to blame and demonize some group or some person; as we’ve seen throughout history, we most often point the finger at those who are not like us.

How would evidence like a chalk-written message on a building entryway be captured? It should have been saved then, as it would be today, using forensic photography.

Photography was well established by then, and there are many images related to the Ripper murders available, including morgue photos of victims.

But unbelievably, because of the darkness of the early-morning hour, the wait time for the arrival of a photographer, and the fact that the shop owners were beginning to open their market stalls, the police decided instead to just copy down the writing and then obliterated the message at 5:30 in the morning. They feared if crowds saw the message, there would be a riot against the Jewish community, and more lives might be lost.

While their anxiety is understandable, destroying potential handwritten evidence like that is wrong. Many Ripper scholars believe, though, that the graffiti may have already been there, especially since some observers said it was blurry. It also may have been a complete coincidence that the piece of Eddowes’ apron was dropped in the same location. Either way, there was heavy criticism of the police’s decision to eradicate the message.

Learn more about how faulty eyewitness identification is the most common source of wrongful convictions in the legal system

Another interesting forensic aspect related to this writing was the early use of forensic linguistics, the study of language. Based on the spelling and grammatical errors, the police commissioner felt strongly the graffiti did not come from a native English speaker.

He wrote in his report, “The idiom does not appear to be English, French, or German, but it might possibly be that of an Irishman speaking a foreign language. It seems to be the idiom of Spain or Italy.” Given the odd phrasing, this makes complete sense, but it’s interesting to note the use of language to help profile the suspect. The nonsensical nature of the wording led authorities to two possible conclusions: If the killer wrote it, Jack the Ripper was Jewish and bragging of it, or the killer was trying to thwart the investigation by blaming a Jew.

A Grisly Delivery: Jack the Ripper Trophies

Due to the killer’s anatomical knowledge, some ascribed to the mutilations and the trophy removal, and the allegations that the Ripper may be a Jew, some began to suspect the killer was a Jewish slaughterhouse worker. Perhaps to help satisfy the public, the police rounded up the knives of the local Jewish slaughter-men to see if any matched the suspected weapon.

A doctor concluded that none of them seemed to be the murder weapon, so we see evidence of early attempts to match a sharp tool with a wound, something common in forensics today, although typically far more reliable when analyzing trauma to the bone, rather than soft tissue.

Picture of the "From Hell" Letter postmarked 15 October 1888.
The note that was sent along with a half a kidney to Whitechapel Vigilance Committee. (Image: By Unknown1/Public domain)

Nearly two weeks after the night Stride and Eddowes were killed, the chairman of the Whitechapel Vigilance Committee got a package containing half a kidney. It was preserved in wine and assumed to be human. Along with this was a note full of spelling errors that explained the other half had been eaten by the killer. But about the kidney, how could forensic science establish this organ as belonging to a human?

Based on my many years of teaching anatomy, using both human and non-human organs for dissection and microscopy, I can tell you that a pig kidney, or that of any similar-sized animal, is very like that of a human. Today’s DNA testing, as well as much faster antibody testing, could allow investigators to quickly determine the animal source, although there is no way to tell how pickling an organ in wine might affect those tests.

Learn more about three of the most important kinds of flawed evidence: false confessions, mistaken eyewitness identification, and flawed “expert” evidence

But the best they could do in 1888 was a microscopic examination, something commonly done in autopsies today to look for pathology, but not to try to figure out the species. Two doctors independently verified the kidney was human, but based on the portion they had, the doctors were not specifically able to match it to Eddowes’ body at her truncated renal artery. They couldn’t say for certain it was her missing kidney, but they also couldn’t prove it wasn’t.

The Making of a Murder Sensation

Image of a newspaper broadsheet referring to the killer as "Leather Apron", September 1888
Newspaper broadsheet referring to the killer as “Leather Apron”, September 1888. (Image: By Unknown – British Museum/Public domain)

Why was the Jack the Ripper case such a worldwide media sensation, even back in the 1880s—in addition to how horrific it was? Any idea why these murders are among the first to prompt copycat killings? Why this case ultimately included a series of letters claiming to be from the murderer?

There is a continuous interplay between science and society. For example, how forensic advances, in both crimes and the technology used to solve them, are directly correlated with other changes in society.

The simple reason this series of brutal murders became the best-known criminal matter of its time was the concurrent boom in newspaper circulation in the second half of the 19th century. Advances in printing and tax reform in England allowed unprecedented low-cost newspaper production and distribution.

Since London was arguably the most prominent of capital cities in the world at that time, it had dozens of newspapers—The Lancet, Times, Daily Telegraph, Daily News, Evening News, Standard, Star, Echo, Lloyd’s Weekly, East London Observer, East London Advertiser, Jewish Chronicle, Jewish Standard, and a whole host of others. Even one publication called the Illustrated Police News, which was an early type of true-crime magazine.

In addition to the newspaper industry, a big reason word of the Ripper’s killings spread worldwide so quickly was that this was also the time of advances in the telegraph technology, including intercontinental communications. The 19th century also witnessed many advances in photography. Accordingly, the Ripper murders coincided with the era when modern journalism was born.

After the discovery of Polly Nichols’ mutilated body, news of London’s East End crime wave spread quickly. Newspapers across the globe picked up that story and the related ones that came with each killing. In fact, the infamous name of this still-unknown killer was delivered to the newspapers. It came in the form of a letter written in red ink to London’s Central News Agency organization on September 27, between the second and third murders among the canonical five.

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The letter’s author took credit for the prostitute killings, saying he would cut off the ears of the next victim, and was signed, Jack the Ripper. Later, on October 1, a postcard in the same red ink and handwriting was delivered to the news agency about the “double event,” alluding to the deaths of Elizabeth Stride and Kate Eddowes in the same night, even saying that “number one squealed a bit, couldn’t finish straight off. Had not the time to get ears for police.” Although Eddowes’ ears were not removed, one was definitely cut.

But then, as now, many who have delved into the Ripper murders believe the letter and the postcard were part of a hoax. Most attribute them to someone in the media, a journalist who had inside knowledge of the events and wanted to sell newspapers. And sell papers they did. Mary Jane Kelly’s boyfriend told police she regularly asked him to read her the news of the killer from the local papers. Little could either one know that she would soon be front-page news as the Ripper’s final victim.

Common Questions About Jack the Ripper

Q: What was Jack the Ripper’s actual name?

Jack the Ripper was actually Aaron Kosminski.

Q: What made Jack the Ripper stop killing?

The current theory is that Jack the Ripper stopped killing because he was close to being caught and he knew as much.

Q: What was Jack the Ripper’s method for killing?

Jack the Ripper killed mostly prostitutes. He would cut their throats and then mutilate the bodies.

Q: What did Jack the Ripper do to the female victims’ bodies?

Jack the Ripper would surgically remove various organs such as the fallopian tubes, uteruses and kidneys from his victims, and display them, seemingly in an act of abhorrence for the female form.

This article was updated on October 9, 2020

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