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On the scene: the Crime Scene Investigator

This month’s interviewee is Joey Giddings, who’s been part of ‘Team Fawley’ from the first book. What he doesn’t know about crime scene investigation isn’t worth knowing, and believe me, some of it you’d actually rather not know at all… He reads all the books at first draft stage, but I often consult him when I’m developing the initial idea as well – so much of modern crime turns on forensics that you can’t afford to base a whole plot on a piece of evidence that simply won’t hold water. But if I’m really lucky, I’ll ask Joey about a new idea and he’ll say ‘Now that’s a really good question”. That’s when I know I could be onto a winner!

Joey and I both did some filming for BBC Ideas in Oxford this month, talking about the fact and fiction of forensic science, and what’s now being described as the ‘CSI effect’. I caught up with him over a coffee after he’d finished recording, and asked him some of the questions suggested by my followers on Twitter and Instagram, as well as a few of my own…

I’m going to start with one from Instagram. It’s from @theweebarrellsbooks, who asked ‘What made you choose this as your career?’

When I was about 12 I decided I wanted to be a policeman, and as I got a bit older I got seriously into science. My first choice of degree subject was actually Egyptology. It sounds a bit left-field, I know, and when I thought about the course in more detail I realised that what had started me off was that scene in The Mummy where the archaeologist unrolls all his brushes and tools. In other words, it was the kit that appealed to me rather than the course! From there it was a fairly quick jump to realising that I could combine my interest in policing with my fascination for science, and the degree I did in the end was a BSc in forensic science at the University of Lincoln. And after that I got my first job working for South Wales Police in Cardiff.

Presumably a CSI has to do professional training as well?

It won’t surprise you that crime scene investigation is a very practical profession, and a lot of the training is on the job, so it depends what sort of job you’re doing. Forensic science is a very varied profession with a lot of specialisms – fingerprint experts, lab technicians, people who specialise in DNA or fibres or blood pattern analysis, or whatever. There’s also a more senior level of ‘Reporting Scientist’, where a traditional science degree like biology or chemistry is the usual educational requirement. These are the people who interpret what the CSIs find, and are qualified to give evidence about that in court.

Other roles require years of continuous training, fingerprint examiners, for example, follow a dedicated training programme that lasts about three weeks, then spend a couple of years in the field, followed by a second course, a couple more years’ work, and then a final course which qualifies them as ‘Fingerprint Experts’. Other areas require such in-depth niche knowledge that we call in specialists from outside the police – if we have a case that involves establishing time of death from insect activity, for example, we might well bring in entomologists from the Natural History Museum in London.

Is the reality of the job at all like what we see in crime dramas? Is there anything that gets you shouting at the TV?

The way TV presents crime scene investigation has got a whole lot better in recent years. Line of Duty now has everyone wearing full white suits, hoods and face masks, which is a big step forward (that used to be my pet peeve). The thing most programmes still get wrong is the amount of time it all takes. Investigating a crime scene is a painfully slow, methodical and often boring process, but you’d never guess that from what you get on screen (or in most books). It’s absolutely vital that we record a complete picture of the scene, and that nothing is moved or interfered with until that happens. One of the main reasons for this is what I said earlier about the Reporting Scientists: they rarely go to the actual scene – all they see is the information we give them, so it’s crucial that it’s both complete and reliable. That means making detailed notes, taking photos and videos, and sometimes drawing floorplans and sketches like the ones I did for In The Dark.

I understand why TV drama has to move faster than real life but it does lead to some basic misconceptions about what we do. Even an urgent DNA test, for example, takes an absolute minimum of nine hours, and that’s only if you get the sample to the lab first thing in the morning. If it’s a mixed sample it can take days to get reliable results. Likewise fingerprint comparison doesn’t involve images of prints flashing up on a screen and a machine beeping that it’s got a match. Fingerprints aren’t analysed like that – they’re assessed on the basis of their salient features, rather than the whole print. When you input those features into the database it’ll come up with around 15 possibilities that match those features. It’s only at that stage that the fingerprint examiner would go and look at those actual prints, and even then the assessment of whether any of them are a match is done manually, not by a machine. It’s a really good example of how much of what we do is dependent on the human angle – the technology is getting better and faster all the time, but there’s always going to be a significant element of judgment and interpretation, and only humans can do that.

The other thing that doesn’t always get done correctly on screen is the post-mortem process. The important thing to remember here is that in forensic terms a crime ‘scene’ isn’t just the place where that crime occurred, it’s anywhere where there might be evidence. That includes the body of the victim, the suspect, and any other relevant items, such as the suspect’s car. They’re all ‘crime scenes’. So a pathologist would usually do an autopsy in the presence of mortuary assistants, a police photographer, and at least two CSIs: the ‘dirty’ CSI assists the pathologist with the collection of samples, and the taking of swabs and scrapings, and these are then bagged and labelled by the ‘clean’ CSI, to ensure there’s no cross contamination.

A question from Twitter now – from Diane Nowell @copywrittencouk. She asks ‘What parts of the forensic ‘story’ can authors fudge (time of death, maybe?) and what details do they have to get spot on for the purposes of believability?’

The best way to answer this is to talk about what we do with the Fawley books. When you ask me a question my first instinct is always to ask what the context is, and what you want to achieve. In other words, what role is the forensic evidence playing in the story. Once I know that I can help ‘work backwards’ to find the best way to do that, while remaining faithful to the forensic process. So to answer the question: it depends on the overall importance the forensic evidence plays in the wider context of the plot. I think one of the successes of the Fawley books has been the willingness to consult with an actual forensic practitioner (and indeed the other advisors), which allows for the true appreciation of the subject matter to be evaluated. I don’t think that is something that can be done purely from researching in isolation.

Another Twitter question, this time from @_tomsouthern. He says ‘Is it SOCO or CSI? Also, can you tell how old stored blood is, e.g. blood in a bag kept in a fridge? Does the DNA of such blood change at all, if so, in what way?’

It’s CSI now. We used to be called SOCOs (Scenes of Crime Officers) but that changed about ten years ago. And that was all down to the American TV series. Gil Grisham et al. made crime scene investigation ‘sexy’ and UK police forces started changing the names of their teams.

As for blood – the DNA profile cannot change, irrespective of how long a sample is stored, but it can degrade, which makes it less useful or even completely useless as evidence. Extreme heat or cold can both contribute to that process. I’ve never known a blood specialist offer an opinion on the age of a particular blood sample, so I suspect there isn’t a scientifically valid way of doing that.

One from me now – in my next book, All the Rage, there’s an element of digital forensic work which you helped me with – is that something a CSI would typically handle or is there a specialised team for that as well?

Digital forensics is a massive field and it’s growing all the time. Just think how many devices we all have as a matter of course – phones, smart watches, tablets, satnavs – never mind the network of servers and the Cloud. And within each of those types of machines and devices there’s a whole range of different manufacturers and models, all of which are being updated all the time. That’s why we need dedicated teams covering digital forensics. The evidence it can give us is invaluable, but you need specialist data analytics skills to get at it.

Another Twitter question – from @miriamcoley4. She asks ‘Do you remember the scene in huge detail and then get flashbacks?’

As I explained before, my job is to make meticulous records of the scene, so having written everything down, I don’t find I remember it in a lot of detail later. There are some things that will stay in your mind, especially if they’re especially unusual or upsetting, like anything involving children, but I’ve never actually had a flashback or a nightmare. And I have to say the support you get within the police is really good. If you’re involved in a particularly distressing case you always go through a TRiM process with the force’s psychologist (‘Trauma Risk Management’) and that also happens once a year as a matter of course. There’s always support there if you need it.

One from Instagram now – from @nim_wat. The question is ‘If evidence is missed or isn’t accepted by the CPS what’s the impact on the CSI team? Is there any blame or criticism or do people accept it as part of the job?’

In practice, you’re very unlikely to miss physical evidence (blood spatter, say, or a weapon left at the scene). And if you did, it would be professional negligence, which would have obvious consequences. What’s much more problematic is so-called ‘trace evidence’. It’s a maxim of the job that ‘every contact leaves a trace’. But by definition you usually can’t see any of that with the naked eye. So all you can do is take swabs of all surfaces that might reasonably be considered to be relevant. You couldn’t swab 100% of all surfaces even if you wanted to – there wouldn’t be the time or the resources – but that means that if there’s something in a bizarre place like on the ceiling, and there was no logical reason to test there, then yes, technically you could ‘miss’ it.

As for it not being accepted, I assume that you mean the CPS rejecting your evidence as not good enough in some way. I’ve almost never seen that happen – it’s certainly never happened to me. But if it did happen then there would likely be an internal police investigation into the CSI’s actions with sanctions ranging from a written warning to instant dismissal for gross misconduct.

And finally, one suggested by your partner! ‘What can a member of the public do to help protect evidence in a crime scene?’

Don’t touch anything! That said, if it’s out in the open and raining it’s really helpful to cover any evidence, ideally in such a way that the cover doesn’t touch what’s underneath – some sort of ‘tent’ arrangement, if you see what I mean. But if all else fails, plastic bags are better than nothing. And wear carrier bags on your hands when you do it, but make sure you turn them inside out.

Why? Because there’ll always be trace evidence on the outside of a carrier bag. Thanks to Joey, I know all about that, as you’ll find when you read All The Rage

Cara Hunter. author of The Whole Truth
Cara Hunter. author of The Whole Truth
Cara Hunter

Cara Hunter is the author of the Sunday Times bestselling crime novels Close to Home, In the Dark and No Way Out, featuring DI Adam Fawley and his Oxford-based police team. Close to Home was a Richard and Judy Book Club pick, and Cara’s novels have sold more than half a million copies worldwide. Cara’s fourth novel, All the Rage, is out soon.

Follow Cara on Twitter.

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