By Fiona Pepper and Claire Slattery for ABC's Big Ideas Podcast
Thanks to fictional crime dramas, the general public has unrealistic expectations around the process of forensic investigations. (file image) Photo: Getty Images / Jacob Wackerhausen
We've long had a morbid fascination with murder and crime.
This has become even clearer in recent years with the popularity of long-running television crime shows like CSI: Crime Scene Investigation and Silent Witness.
So how close is TV crime drama to the real thing?
WARNING: This story contains content that readers may find distressing.
Three forensic pathologists tell ABC Radio National's Big Ideas what it's actually like to work in the field.
And spoiler alert: These experts say there is no crime drama that comes close to the real thing.
What is a 'CSI moment'?
"What you see on television is … forensic pathologists where they know everything and they chase [suspects] down the road, etc … In reality, we don't even get to know the DNA results," associate professor Linda IIes, the head of forensic pathology services at the Victorian Institute of Forensic Medicine, explains.
According to Dr Iles, the most far-fetched example is Silent Witness, where lone forensic pathologists often "skulk around crime scenes at night".
"Initially I had some affection for that show … but some things should end because it's just becoming more and more crazy," she says.
The other gripe that these forensic experts have is around what is dubbed a "CSI moment".
A CSI moment is when a forensic scientist provides the information that supposedly cracks open a case single-handedly - they're the bread and butter of forensic fiction.
But in reality, these forensic scientists say they experience a moment like this once or twice in a lifetime, if at all.
Forensic entomologist and pathologist Melanie Archer says you're more likely to have "a lot of little tiny CSI moments".
"As a forensic practitioner … there are lots of little wins that add up to the big win …[For example] I might be able to tell the police something that is useful to them in their investigation," Dr Archer explains.
She points out there have been some famous real-life CSI moments in forensic entomology that now "don't stack up".
"You look at them and you think, 'Well, that's a bit of an overreach'," she says.
For example, the Sung Tzu case in 1247 was one of the first examples of forensic entomology.
Dr Archer describes the case as "an ad hoc murder trial that was held in a field in China".
Following the murder of a farmer, a local judge ordered that everyone in the village lay down their farming tools.
While the tools appeared clean, one attracted flies and it was assumed that was because it had trace amounts of blood. This was the basis of the murder conviction.
"It just makes me so annoyed if this actually happened and somebody was convicted on the basis of that. I apologise for my discipline because we would obviously never do that," Dr Archer says.
She says as scientists, it's crucial alternative explanations are explored.
For example, in the Sung Tzu case, it could have been a coincidence or a particular pattern on the tool that flies were attracted to or it could have been the blood of the owner of the tool, she explains.
"I can come out with a lot of different explanations and that's one of the things that I really try to do, [to] be the first one to think of the alternatives," she says.
[REALTED]https://www.rnz.co.nz/news/national/528490/the-language-of-forensic-science
Season 14, Episode 2 of CSI: Crime Scene Investigation series. Photo: Alliance Atlantis Communications / Collection ChristopheL via AFP
What actually happens at a crime scene?
Samantha Robotham, a forensic anthropologist at the Victorian Institute of Forensic Medicine, explains that her role at a crime scene is to work alongside archaeologists working on the recovery process.
Then the anthropology examination takes place at the mortuary in consultation with the forensic pathologist.
"Most of the time if the remains are skeletonised … the anthropologist will then look at a number of different features on the bones to answer a range of different questions," Dr Robotham says.
These include estimating the deceased person's sex, age and ancestry to help with identification.
"Then the questions that really come down for the anthropologist would be questions around the preservation of the remains, and are the changes that we see in the bone the result of the environment … or are they the result of trauma? And at what point did that trauma occur?" Dr Robotham explains.
She says if the cause of trauma can't be ascertained, she pieces the bone back together like a jigsaw puzzle.
"If you just have [bone] fragments, it can be very hard to see that an edge of that fragment might indicate that there was a bullet or some type of blunt force event or something else," she says.
"So you can only really understand what happens when you reconstruct and you're looking at the complete bone again."
Dr Iles is an expert in brain injuries and conducts neuropathological examinations via CT scans and MRI.
"I spend a fair bit of time doing brain examinations and then obviously the histology (the work under the microscope) afterwards and that actually, from a neuropath point of view, can be the most time-consuming thing to do," Dr Iles says.
She says, given the complexity of the brain, "it's not a case of, just examine this brain and write a report".
The examination would incorporate a range of factors, as every case has a unique set of questions that need to be answered.
TV crime dramas are so far from reality, they can help to establish unreasonable expectations in the public's mind about forensics. (file image) Photo: 123rf
How insects can provide info
As a forensic entomologist, Dr Archer pays close attention to tiny insects at a crime scene, which may provide her with clues about what took place.
Her main focus at a crime scene is examining when and how those insects colonise the dead bodies.
"[So] you need to be aware of making sure that you collect all those life-history stages that have left the body," she says.
In other words, rather than purely focusing on the body or bodies, it's important to examine the surroundings for insects that may have finished feeding on a body and then crawled away, she explains.
"If you're in a house, you would be looking potentially in cupboards and under carpet and in detritus … just trying to make sure that you find all those little hiding maggots or pupae and potentially even remnants left by dead insects that have been feeding on the body at some time in the past," Dr Archer says.
How the microbes we leave behind on our clothing could help solve murders
Back in the lab, Dr Archer then looks for the age of these insects, which may provide some indication of the time of death.
Then once the body is in the mortuary, she takes all the insects from the body.
"And you can look deeper under the clothing and under better light at the mortuary," she says.
One major consideration is the species of fly that may have colonised on the body, as each fly species has a different growth rate.
And at a crime scene, temperature is also closely reviewed, as that impacts the life cycle of a fly.
Unreasonable expectations
Because TV crime dramas are so far from reality, they can help to establish unreasonable expectations in the public's mind about forensics.
Dr Robotham says her main frustration is the perception that a forensic anthropologist can provide definitive answers.
"That's probably a reflection of fiction because anthropologists are normally very fabulous in fiction at giving exact causes of death and all these sorts of things that do not happen in real life," she says.
This is because every human is unique and "our skeletons are no different", so it's impossible to be definitive when looking at a crime scene.
Dr Iles gets frustrated with the assumption that forensic teams can provide specific information about the time of death as precisely as fictional investigators do.
"I sit directly opposite our family health nurses who speak to families on a daily basis, answering their questions around cause of death and process and the number one question they get asked … is around time of death," she says.
Despite the expectation that this information is available, Dr Iles says it's difficult to communicate the reality of the situation to families.
While the work may not be as dramatic as fictional crime shows portray, she says she is drawn to the problem-solving aspect of forensic pathology.
"It's not the kind of exciting things that people see on television, but the reason why I do this job and got into this job is I enjoy the challenge of finding answers for families and people," Dr Iles says.
"To make a diagnosis which probably wasn't thought of beforehand and being able to communicate that to families … I guess they're my CSI-type moments."
- ABC