The sweat of a single fingerprint can be tested for drugs
Fingerprint identification has been around for centuries, but in the last decade it has become possible for the sweat deposited in a single fingerprint to show what narcotics – or even spices (eg from an Indian meal) were present in the person’s bloodstream at the time the fingerprint was left. Such ‘lifestyle intelligence’ can be especially helpful not only in police investigations but also in more day-to-day procedures such as sports-based drugs testing, roadside testing for drink- or drug-taking, or workplace screening.
Forensic scientists are used to the smell of death
It sounds horrific – working amongst decomposing remains in a quest for knowledge, all in the name of forensic science and evidence. And at first, perhaps it is. The odor of flesh returning to the earth is apparently a sickly sweet kind of smell, but not one many of us would enjoy. However, for those working at human taphonomy facilities such as the Australian Facility for Taphonomic Experimental Research (yes, that spells AFTER), it’s been reported that you do acclimatize to the unique scent.
Diabetic patients can donate compromised limbs to forensics
In Canada, the Ontario Provincial Police have a program with Queen’s University in Canada that accepts live donor amputated tissue from patients with diabetes (one of the more severe symptoms of diabetes is gangrene). This is part of a project run by Shari Forbes, who is in charge of the Canadian human taphonomy facility (otherwise known as a ‘body farm’), where they study human decomposition. Sniffer dogs go through training on how to locate a corpse, and the odor is obviously key to this training.
Bugs can be used in forensic science
This is really unpleasant, but kind of cool too: Forensic scientists can look inside a maggot’s stomach to find out how old its last meal was – i.e. the body it was feasting on. That tells them how long a body has been decomposing. Gross, but also creepily clever, right?
The hair root can identify a person’s gender
Hair is good for evidence, but only the hair root itself gives the marker for gender. That’s because only the root itself contains the DNA of the individual, which is what forensic scientists require in order to establish whether the body was male or female (at the genetic level).
Corpses are sometimes placed outside on purpose
As in, not by the guilty party, but by forensic scientists, for a legitimate (if nasty) reason. People sometimes leave their body to science in their will, so forensic scientists will occasionally use that cadaver to study the effects of decomposition in a certain environment. The chances are that many cases will involve a body left somewhere outside, so forensic scientists want to replicate that with a ‘test’ corpse.
There’s more to blood spatter than what’s shown on Dexter
The forensic science of BPA (blood spatter patterns) encompasses more than one specific kind of stain. The patterns made when blood droplets are deposited via forces other than gravity (eg from a victim to a surface or via cast-off from the weapon) are what most of us think of when the topic comes up. However, blood transfer patterns are the transfer of blood from one item to another eg by the perp attempting to clean up, whilst blood drip stains are pretty much that – gravity taking effect on blood.
Forensic science is prone to contamination
Unfortunately, it is all too easy for DNA evidence to be compromised and therefore deemed inadmissible. How galling that would be for the investigators and police, and how upsetting for the victim’s loved ones, seeking justice. One famous example is the Phantom of Heilbronn from Germany. Police were mystified by the seemingly random crimes that the supposed perpetrator left their DNA at, but the DNA turned out to belong to one innocent (if careless) worker at the factory that made the swabs. Whoops.
Teeth are the best way to identify someone
Teeth, which are basically bones (made from calcium and other minerals), can take decades or even centuries to fully decompose. Using teeth as an identifier is also incredibly accurate – as much as 93% of the time. That’s a pretty convincing record.
Glitter is great for trace evidence
It gets absolutely everywhere, it’s terrible for the environment and it’s hard to completely clean up. Yet in rare instances, it’s fantastic as trace evidence. That’s because it transfers so easily from person to person, doesn’t biodegrade and is relatively easy to spot by a decent investigator with a working torch. As unusual as it might be for glitter to be evidential, it has happened. At least it’s good for something.
The blue substance you see on TV does exist
How often do you watch shows like CSI or Blue Bloods and wonder if the tools of the trade they use actually exist? Well, the part where they sprinkle powder around and it turns blue is legitimate – it’s called luminol. It is used at crime scenes to detect small amounts of blood, and it works by reacting with the hemoglobin in the blood. When that happens, it glows blue, known as chemiluminescence. Gruesome but cool.
You can specialize in the area of ‘blood splatter’
This is a genuine field of forensic science – specifically analyzing the splatter of blood and blood stains at a crime scene, which helps to provide insight into what happened to the victim during the crime. It might sound disgusting, but it’s an important area when it comes to solving crimes. In fact it’s pretty well known now due to various TV shows such as Dexter.
Forensic science has existed for centuries
In the 13th century, a Chinese judge named Song Ci wrote a book called The Washing Away of Wrongs. He documented how he had used forensic entomology (the use of insects) to find the murderer of a victim who had bled to death. He first tested different implements on a corpse to pinpoint a sickle. Then he asked the villagers to show their sickles. Flies rushed to one in particular (yuk), and the owner confessed. Gotcha.
Forensic science can help with many crimes
Forensic scientists are involved in other crimes, such as arson and assault. In 2013, one scientist developed a fluorescent dye that showed lacerations to the skin regardless of skin color, which has subsequently been included as part of evidence kits. Prior to that, the dark blue dye used was only effective on white skin, so having a test that works on all ethnicities is a huge forensic advance.
Forensic scientists can help with environmental cases
Sometimes, nastiness such as raw sewage or toxic pollutants end up in our rivers and waterways. Have you seen Erin Brockovich? The film was based on a real case, and according to the real Ms. Brockovitch, was “probably 98% accurate”. Forensic scientists can be brought in to test what’s in the water that is killing off wildlife or affecting local residents.
Sniffer dogs can smell out a dead body
Certain dogs, known as ‘decomp dogs’, can be trained to sniff out a dead body, via the use of a synthesized chemical that simulates the inimitable smell of a corpse. And for those situations where it wouldn’t be ethical to use an actual dog, such as battlefields, a device called LABRADOR (Light-weight Analyzer for Buried Remains And Decomposition Odor Recognition) exists, to reunite deceased soldiers to be repatriated and reunited with their families.
Forensic science can get down and dirty
This is one grubby little forensic fact…quite literally. Forensic scientists can test soil samples found on clothing and match it to the soil found at a crime scene. How do they do that, you might wonder. Well, specific microbes found in the soil samples can be checked and matched (or ruled out) with microbes from the soil at the crime scene. Dirty, but precise – vital in terms of evidence.
Forensic training includes The Nutshell Dioramas of Unexplained Death
As macabre as this might seem, there exists a set of 19 different dollhouse-sized dioramas showcasing actual death scenes from historic crimes. They were created in the mid-1900s by forensic pioneer Frances Glessner Lee specifically for training investigators. They’re so realistic that the diorama corpses accurately represent discoloration or bloating that would be present at the crime scene. The dioramas are still used for training, principally at the Maryland Medical Examiner’s Office in Baltimore.
Forensic ‘body farms’ exist to study decomposition
In some countries (including the US), forensic scientists have specific places where they study the effects of decomposition based on the different conditions a corpse is left in. Officially known as human taphonomy facilities, the first was set up in Tennessee back in 1981, and one of the most recent opened in Quebec in Canada. It sounds gruesome, but from a forensics perspective it makes good sense. Some countries still use pig bodies, but human cadavers are, unsurprisingly, the most accurate.
A person’s death is as unique as their life
Just like in life, a person and their body’s decomposition is unique, as forensic scientists studying the subject have found. A person’s age, diet, gut bacteria and other factors (such as regular prescription meds and treatment for illnesses such as cancer) all have an effect on how that body will decompose. Inconsistency in science brings questions of reliability, so some forensic scientists question the validity of the findings.
Forensic scientists have a dark sense of humor
In a line of work that requires incredible attention to detail, meticulous adherence to legislation and all manner of unpleasant and upsetting scenes, it would be quite important for your mental health to have a sense of humor. Forensic scientists understandably keep theirs professionally stowed out of sight whilst at work, but it’s there. In one lab at the university of Quebec, a tongue-in-cheek sign on the fridge reads ‘WARNING: IF YOU ARE HUNGRY DO NOT EAT WHAT IS INSIDE.’
Cadaver dogs can be better than technology
Forensic science has come on leaps and bounds in the centuries since the Ancient Romans first tried it, but sometimes nature is still the best. In 2010, sniffer dogs (also known as cadaver dogs or decomp dogs), were instrumental in a case in London, UK, where ground-penetrating radar had not found anything. Cadaver dogs had shown an interest in a specific area though, and a body was discovered buried on the site.
Every forensic scientist has at least one nasty story
Not every forensic scientist works on murder cases. Nevertheless, chances are that most forensic scientists will have at least one gruesome recollection from their time in the job. One forensic scientist, whose department only worked on burglaries, reported how she had gone to investigate one case and found a glove with something hard inside. Upon shaking it, a human thumb fell out. Apparently one of the burglars, holding up a safe, managed to drop it on his hands, which led to him losing his thumb when he fled.
It’s an assumption that no two fingerprints are the same
Despite a widely held and accepted belief that no two fingerprints are the same (with the exception of identical twins), it isn’t a proven fact. The reason for this is because there has never been a scientific study to verify the statement. It has been taken for granted, given that, according to Simon Cole (a professor of criminology, law, and society), fingerprinting experts have never agreed on how to measure the rarity of an arrangement of friction ridge features in a fingerprint.
Mistakes happen, but sometimes forensics can benefit
We’re all human, we all make mistakes – sometimes it’s the best way to learn. That was obviously the attitude of the team at the Complex for Forensic Anthropology Research at Southern Illinois University. A lawnmower operator accidentally ran over two of their skeletons. So the team made the best of it and published the effects of lawn mowers on human remains, brilliantly titled Lemonade from Lemons: The Taphonomic Effect of Lawn Mowers on Skeletal Remains.
Not every forensic expert is necessarily decent
Like most people, most forensic scientists are decent people doing their best in their job and in life. Of course, a few people commit the most horrendous crimes – and one forensic expert, Serhiy Tkach, was guilty of committing some heinous offences in Ukraine over a 25-year period. Tkack’s time in the Soviet army and then as a police forensics expert enabled him to get away with a series of murders over a quarter of a century.
Forensic science can help with justice, but not depravity
There’s no doubt that forensics have helped bring justice in many crimes, but it can’t always stop the guilty from continuing with wrongdoings, even from behind bars. DNA evidence was used to bring Arohn Kee to justice for his offences, which were documented in an episode of the Cold Case Files called The Shopping Cart Killer. Kee was jailed for his crimes, but upsettingly he can’t be tried for the ethically dubious act of creating 5×7 cards documenting those offences and then selling them online.
Blood spatter is affected by the surface it lands on
When blood lands on a surface, just like water, the type of surface affects what happens. A fluid landing on bedsheets or other soft furnishings would be absorbed and thus distort the patterns. However, glass wouldn’t affect the pattern (although gravity might), while a concrete floor might prompt “satellite” droplets. A good forensic scientist will take the surface into account along with the other factors.
Forensic science still has a long way to go
Aside from DNA, many fields of forensic science are not 100% reliable, though plenty of convictions have happened largely on the basis of forensic evidence. In recent years, the FBI has scrutinized its own microscopic hair comparison unit, with a review going back to 2012. Other types of forensic evidence have also been queried – pattern matching techniques such as bite mark analysis, shoe and tire markings and even blood spatter evidence. Who knows how many innocent people have been jailed (or even executed) as a result of forensic ‘evidence’.
Some forensic fields need a conviction to get going
There are many disciplines of forensic science, often not widely known, let alone endorsed, when they first come to exist. Forensic anthropology (the study of skeletal or fragmentary remains), was initially dismissed as pseudoscience. However, in 1897, the murder of Louisa Leutgert, wife of Alfred Leutgert, ‘The Sausage King of Chicago’, changed that. When police came to the sausage factory to investigate her appearance, the sickening smell inside a vat prompted the discovery of her wedding ring, and assorted bone fragments. Leutgert was convicted in part due to the forensic evidence.
The latest development in forensics is digital
Developments in forensic science happen all the time, but the most recent field of forensics is digital. It’s unusual for a murder prosecution to happen without a body, but in the case of Suzanne Pilley, who went missing in 2010, digital forensics were enough to get a conviction. Police were able to build a solid case, despite her body never being found, due to unusual mobile activity on David Gilroy’s phone, CCTV and roadside imagery, supported by other circumstantial evidence.
Blood splatter forensics got more credence in the 1950s
Bloodstain pattern analysis (BPA), based on the physics of fluid spread and movement, is a science that wasn’t taken seriously for a long time. However, a study in 1895 by Eduard Piotrowski – using some unfortunate rabbits – gave more weight to it, and then a murder case in 1954 enhanced its plausibility. The forensic science pioneer Dr Paul Kirk had given testimony that a single blood stain on the knee of a victim’s husband was not in keeping with the extensive amount of blood at the crime scene, and BPA became a legitimate tool in forensics.
Forensic scientists sometimes have to seek assistance
Occasionally, forensic scientists draft in experts in unusual areas in order to obtain the evidence needed for a court case. In one such example, British forensic anthropologist Dr Julie Roberts sought help from a structural engineer, who was an expert in concrete. This was for an unusual and macabre case of a body entombed in layers of concrete and concealed within a purpose-built retaining wall. The concrete evidence (no pun intended) that was secured enabled the conviction of four men.
The forensic science of odontology isn’t an exact science
In recent years, various fields of forensics have been called into question for their reliability, leading some cases to be overturned and the whole area to be cast into disrepute. With the exception of DNA fingerprinting, it’s now more widely accepted that forensic science is often best used as supplementary evidence, in support of a witness’s testimony. The study of bitemarks (odontology) falls in this remit, and when a trial was done to see whether dental experts were better at bite mark analysis than students, the results were mixed.
Beetles like to eat dead bodies
The forensics of studying insects that eat cadavers goes back centuries, and is one of the more scientifically accurate practices within forensic science. One specific sub-set of bone beetles are partial to decomposing flesh, while dermatid beetle larvae enjoy skin and hair due to their unusual ability to digest keratin. Food for thought for anyone that bites their nails.
Alphonse Bertillon was a founding father of forensics
Alphonse Bertillon’s ‘God’s eye view’ brought much-needed methodology to the use of photography at a crime scene. He devised a method of photographing crime scenes with a camera mounted on a high tripod, in order to document it before it was disturbed. He also created the first approach of identifying criminals, by using body measurements, when prior to that it was only through names or photographs, which were easy to fake.
DNA fingerprinting has unsettling implications on privacy
As much as we want to see serial offenders and violent criminals brought to justice and appropriately incarcerated, the use of DNA in forensics has a darker side. Granted, if you’re a law-abiding citizen just going about your life, it probably won’t affect you, but you may not know that in 2019, a well known personal genetic service admitted to sharing DNA data with federal investigators? OK, to help solve crimes – but would you want your genetic make-up shared with the FBI?
Blood spatter analysis can help pinpoint the weapon
Sometimes the weapon used at a murder is not immediately obvious, and sometimes it’s never found. However, the pattern made by the victim’s blood can provide certain clues, including regarding the kind of injury sustained. A high-speed spatter made up of tiny drops is likely from a gunshot, where as medium-velocity stains are more likely from a blunt object or fist, or maybe even from a severed artery.
Forensics isn’t just inspiration for TV and movies
You may have heard of Patricia Cornwell, the American crime writer who has written 27 novels featuring medical examiner Dr Kay Scarpetta. Having worked at the Office of the Chief Medical Examiner of Virginia for six years, Cornwell evidently picked up significant knowledge, as her books are forensically quite detailed. In fact, one of her books was the inspiration for the term ‘body farm’.
Forensic training in blood pattern analysis needs better certification
It’s one of the oldest forensic sciences going, yet even in this modern day there is still room for error in the subject of BPA (blood pattern analysis). Back in 2009, the National Academy of Sciences (NAS) published a report on how forensic science in the USA needed improving. Specifically, the NAS noted the complexities of fluid dynamics and that BPA analysts should comprehend the relevant physics. However, there is no specialization training for BPA experts, which leaves it rather more subjective than scientific.
