Tools of the Trade: Crime Scene and Forensic Investigators

Nominated BEST TRUE-CRIME PODCAST at British Podcast Awards 2018, The Telegraph's Top Five True-Crime Podcasts, The Guardian's Podcast of the Week and iTunes Top 25. Subscribe via iTunes, Spotify, Acast, Stitcher and all podcast platforms.

So, what are the useful pieces of kit used by Crime Scene Investigators and Pathologists. Let’s start with some simple things which crime scene investigators carry:

The standard kit that all crime scene investigators carry with them includes; stationery (such as pens, pencils, a notepad, graph paper, a small ruler, permanent markers, spray paint and chalk) to mark the scene, evidence and make any notes. As well as a torch, a camera, flares, a tape measure, a small set of scales, a latent print kit, a bodily fluid collection kit, a footwear casting kit, bindle paper, tweezers, syringes, knife-tubes and biohazard bags (all used to safely collect and retain evidence, using labels, tapes and seals) as well as the protective equipment they will be wearing (including gloves, booties, hair net, overalls and mask) to prevent cross-contamination. Crime scene investigators also carry Police tape, but the crime scene will already have been sealed-off by the first responders.
These are just the basics, but what other fancy tools do they have at their disposal.
 
The Bullet Puller; in any shooting, it’s important for the investigator (at the crime scene) to establish what type of bullets they are, who made them and when, and the gunpowder and the wadding used is vital to determine this. The problem is that when bullets are ejected from a casing, the wadding is often lost or destroyed. But if unfired cartridges are found, as it is difficult to remove the wadding without damaging the casing, the investigators can remove it safely using the Bullet Puller. It’s like a plastic hammer with a hollow head, and once the bullet is loaded in, the cartridge is whacked hard, the bullet, the casing and wadding separate and the three components are undamaged. Anyone can buy a Bullet Puler, in fact, they’re available via Amazon.

Phenolphthalein: way before a CSI attends a crime scene and sprays objects with Luminol, a chemical which reacts with the haemoglobin in blood causing it to become florescent (as discussed in Mini Mile 1) and a substance which can corrode or destroy evidence if used incorrectly. Each CSI comes equipped with a simple blood testing kit, so with a very small swap of Phen-olph-thalein and hydrogen peroxide, they can determine from the sample’s PH balance if it is human blood; if it turns a bright pink, it’s blood, and they won’t have compromised the crime scene or the blood itself, as Luminol can do.

Gas Chromatograph–Mass Spectrometer. This is not something CSI’s have in their car, but back at the lab. It’s a very technical bit of kit, so I’ll explain it as simply as possible. In short, a GCMS can take a tiny sample of any unknown substance, and when the sample is placed inside the GCMS’s isolation tube, gas pushes the chemical components of the sample slide at one end of the tube to the other, and by determining the speed, weigh and density of these components hitting the sensor, this tells them what each of the chemical components are.

Laser Ablation Inductively Coupled Plasma Mass Spectrometry (known as LA-ICP-MS, let’s call is Laz-Abs): When broken glass is found at a crime scene, although visually you can take an educated guess at how it was broken, it’s hard to accurately tell what direction, speed, angle, height and with what object the glass was broken. But by analysing the atomic structure of each fragment, the Laz-Abs is able to compare and match each fragment, to give the specialist a clearer picture of how the glass would have looked at the point of impact.

Alternative Light Sources (known as ALS): before an autopsy takes place – a procedure which is incredibly invasive and can destroy evidence if it is not spotted) – so without moving or disturbing the body, even at the crime-scene (in a limited capacity) a forensic nurse is able to assess the physical damage to a human cadaver by using ALS. As you know, light is made up of different bands, covering visible and invisible light rays, ultra-violets, infra-reds etc, and as different objects, colours and temperatures give off different light signatures, these can be seen by using different filters on a camera. So if there is bruising underneath the skin, not visible to the naked eye, it will be visible in ALS.

Digital Surveillance For Xbox (XFT): For those who love playing video games, inside all games consoles which have internet capability is a hard-drive which stores all useful stuff like high scores and positions in the game, but also the dates, times, location and duration of your game-play, as well as the images and sound of your game play. This is a system accessible by digital forensic specialists and these recorded sessions have been used to prosecute people in court trials.

Video Spectral Comparator 2000 (you know it’s very technical as it’s suffixed by the numbers 2000, wow, I bet it uses a “laser”). The VSC 2000 is a Super Resolution Imager which allows investigators to examine a piece of paper at a macroscopic level to identify the paper’s origin, quality and type, and identifying the unique signature of a person’s handwriting, any alterations or deletions, even if the paper has been damaged by fire or water. The VSC 2000 has since been replaced by the VSC 8000. I know! 8000, that’s four times better. Wow!

Phenotyping. Phenotyping is a process of predicting genetic information based on the DNA sequencing, this allows the investigator to predict a person’s hair and eye colour based on 24 DNA variants and six genetic markers. It’s not fool-proof yet, but the HIrisPlex system can predict blonde hair 70% of the time, brown hair 79%, red hair 80% and black hair 88%, giving any investigator a set of parameters to work from, based on a small sample of DNA.

Microbiomic Identification. It currently isn’t accurate enough to use in an investigation, but as our bodies have roughly 37.2 trillion cells each, and twenty times more microorganisms known as microbiomes than we have cells, and everyone’s microbiomes are unique to each person, and each colony of microbiomes is unique to a specific part of their body – phew - investigators are currently trialling a system of identifying a person by a single microbiome. It’s early days but it is believed to be the cutting edge technology to help convict those who commit sexual assaults.

Tattoo ID. For no fathomable reason, loads of criminals seem to think it’s a genius idea to get very distinctive tattoos, often on their hands or face, and although these are often obscured by clothing or are difficult to see on poor CCTV, TattooID is a high-resolution spectral imaging system which scans the finer details of tattoos taken from CCTV, collects them into a database and (as each tattoo is drawn by hand, therefore they are all unique) it is proving to be as accurate as fingerprinting.

Palynology. No matter where you walk, whether a forest, a field or a street, there are a wide variety of trees, plants, weeds, flowers, fungi and grasses, drifting through the air seeking places to settle and spawn, but often they land on your clothes, your hair, your skin and your shoes. And although they might seem insignificant, these pollen biomarkers give off a specific “signature”, linking a unique collection of pollen to not just a place but also to a time. Pollen Biomarkers were effectively used to determine the origin of hundreds of victims found in mass graves in Bosnia.

Vehicle Systems Forensics (VSF). Every criminal knows not to use their mobile phone when committing a crime as the phone stores all kinds of data such as date, time, speed and location, as well as what you’ve searched for. But as phones get smarter, so do our cars. Most modern cars, not only contain inbuilt GPS and infotainment systems, but also a telematic system. This is a small hidden box complete with 70 interconnected electronic control units placed throughout the car, which informs the driver about all manner of interesting details; such as, if doors are open, seatbelts unbuckled, air-bags, air-con, engine speed, distance, direction and duration…but this data is also collated by the system for diagnostic purposes… and can tell any crime scene investigator where you’ve been, when and how.

So, if you’re a criminal, who spends all day in a field of wild flowers, scratching the microbiomes off your head, driving whilst texting and instagraming your entire escape from the Police, having got a tattoo of your name, address and a list of crimes on your face (although I wouldn’t put it passed some of the numpties out there), you’re screwed. If not, you’re still screwed.

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Nominated BEST BRITISH TRUE-CRIME PODCAST 2018, iTunes Top 50 Podcast, Crime Read's "Essential Crime Podcast of 2018", The Telegraph's Top Five True-Crime Podcasts and The Guardian's Podcast of the Week

Michael J Buchanan-Dunne is a writer, crime historian, podcaster and tour-guide who runs Murder Mile Walks, a guided tour of Soho’s most notorious murder cases, hailed as “one of the top ten curious, quirky, unusual and different things to do in London”, nominated "one of the best true-crime  podcasts at the British Podcast Awards 2018", and featuring 12 murderers, including 3 serial killers, across 15 locations, totaling 50 deaths, over just a one mile walk