Gut Feeling

This is my last blog of 2012, and as it is the festive season, I'm going to write about intestinal micro-organisms!

 

We humans live with a large population of micro-organisms in our intestines.  Collectively known as gut flora, they perform a variety of useful functions, such as extracting nutrients from food, training the immune system to respond only to pathogens and preventing the growth of harmful bacteria.

Now, researchers at Washington School of Medicine in St Louis and the European Molecular Biology Laboratory in Heidelberg, Germany, are suggesting that our gut flora may have an important part to play in forensics.  Just as our DNA varies from person to person, so, apparently, does the DNA of the micro-organisms in our intestines.  This means that a person may be identifiable from the DNA profile of their gut flora.

Here is an account of the research:

New Genetic Fingerprint lives in your Gut

Clearly, the overall purpose of the research is to improve human health.  But advances in forensics often come from unexpected sources.  The revolutionary approach to developing invisible indented impressions of writing on paper arose, almost accidentally, from research into latent fingerprint development techniques.

So, if one of your characters leaves a series of anonymous letters smeared in excrement in a number of other characters' mailboxes (it does happen), maybe this new technique could provide a starting point for the police investigation.  Just a thought.........

If you celebrate Christmas, have a wonderful time and don't treat your gut flora too badly!  Thank you for reading my blog this year, and  I hope to connect with you again in 2013.

Don't forget to follow me on Twitter @forensicswrite.



The Sole Evidence

On 27th July 2008, at approximately 5am, newlyweds Ben and Catherine Mullany were shot and robbed in their hotel bedroom on the last day of their Antiguan honeymoon.  Catherine died instantly; Ben went into a coma and survived long enough to be flown home to Wales, but doctors could do nothing for him.  A week later, his life support machine was turned off. 

Two weeks after the Mullany killings, local shopkeeper Woneta Anderson was shot and killed during a robbery at her store.  All three victims had been shot once in the head. 

The Government of Antigua and Barbuda had called in London's Metropolitan Police to assist with the investigations into the Mullany killings.  Antigua's tourism-based economy was likely to be severely damaged by the killings, unless the case was solved quickly.  Moreover,  Antigua had only one trained forensics officer, who would be under immense pressure without additional expert assistance.   

The Mullany killings were found to be linked to the Anderson killing - all three victims were shot with the same gun.  From the wealth of forensic evidence found at the Anderson crime scene, two local men, Kaniel Martin and Avie Howell, were arrested and subsequently charged with murder. 

After a trial lasting two months, Martin and Howell were convicted of the three killings.  Each man received three consecutive life sentences for their crimes.  At the time of their sentencing, they had yet to be tried for two other charges of causing death by shooting.

One important piece of forensic evidence concerned the partial shoeprints made in blood, which were found at the scene of the Anderson killing.  The forensic examination of shoeprints is a huge subject and impossible to cover in detail in a blog post.  However, here is a report of the shoeprint evidence given at the Mullany/Anderson murder trial, which, I think will give you a good general overview of the topic.

 Shoeprint evidence at Mullany/Anderson murder trial

As is clear from Anthony Larkin's evidence, in order to be able to link a suspect's shoe with a crime scene sole impression, individual features have to be present in both.

Individualisation of a shoe's sole is based upon the knowledge that accidental marks formed during wear are unique.  It is essential that the forensic examiner is well-versed in the shoe manufacturing process, otherwise manufacturing defects could be mistakenly identified as unique wear damage, particularly by an inexperienced examiner.  Cheap footwear is more likely to contain manufacturing defects than expensive brands. 

The surface bearing the shoeprints can affect the quality of the impression.  The wooden floor of Woneta Anderson's store was rough and uneven.  As Mr Larkin pointed out, the damage feature on the sole impression was not as clear as it could have been, because of problems with the surface of the floorboards.

Since footwear impressions are one of the most common types of evidence found at a crime scene, a great deal of research has been carried out to find the best methods for enhancing visible shoeprint impressions and developing latent (invisible) impressions, particularly on difficult surfaces, such as clothing.

Researchers at the University of Abertay in Scotland have recently produced 'the world's first detailed images of latent footwear left on fabrics'.  By adapting and modifying existing visualisation techniques, the researchers hope that their methods will be particularly valuable in cases where no DNA or fingerprint evidence is found.

Read about their work here:

 Shoeprints recovered from crime scene clothing

Finally, a word about automation.  Clearly, the linking of a crime scene shoeprint with an item of footwear is always a task for a forensic expert.  However, reference databases of footwear sole patterns are available for the police and other law enforcement agencies to allow them to identify makes and styles of footwear.  This obviously saves a lot of time and allows a case to move forward more rapidly.

Here are some examples of commercially available shoeprint identification products.

Foster and Freeman's shoeprint identification products

Cape Coral PD in Florida found its shoeprint matching software invaluable in tracking down a serial burglar.  Watch the video here:

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The Scent of Death

Last year, the USA was gripped by the Casey Anthony murder trial.  Anthony was accused of murdering her daughter, Caylee, aged 2, and providing false information to the police.  Caylee was not reported missing for a month, and it was a further 6 months before her decomposed remains were found in woods close to her home.  When the jury reached a 'not guilty' verdict on the murder charge, the country was shocked.  There had not been such a controversial verdict since OJ.  I'm sure you will have your own opinions about both verdicts.

 

One of the prosecution witnesses at the Anthony trial was K-9 Deputy Jason Forgey, whose cadaver dog, Gerus, alerted to the scent of human remains in the trunk of Casey Anthony's car and a corner of her parents' back yard.

Watch Deputy Forgey's testimony here.     

The ability of dogs to locate people and objects by scent has been utilised by law enforcement agencies for a long time.  Trained dogs are used primarily for tracking, searching and locating evidence.  Some dogs are cross-trained for more than one task; others are trained to perform a specific function.

There seems to be some variation in terminology for describing and differentiating between dogs trained for particular tasks, but for the purposes of this blog, I'm using the term  'Cadaver Dogs' to describe dogs which are primarily trained as search dogs, but have also received cross-training in the location of dead human bodies.

By contrast, 'Forensic Evidence Dogs' (also known as 'Human Remains Detection Dogs'), specialise in buried bodies, old homicide cases, bone searches, buildings searches, vehicle searches, crime scene searches, small scent sources and residual scent.  Other forensic evidence dogs specialise in searching for firearms, explosives or drugs.

In forensic work, the breed of dog is less important than its ability to learn, interact with its handler and locate a particular scent.  But a search and rescue dog, for example, needs to be robust, like a German Shepherd.

Both Cadaver Dogs and Forensic Evidence/HRD Dogs are trained to locate the scent of death, which is caused by chemical decomposition.  However, because they are not cross-trained, Forensic Evidence/HRD Dogs are never looking for live scent.  They have been taught to exclude fresh human scent and to ignore all animal scents, whether fresh or decomposed, when carrying out a search.  

Working slowly and methodically, a fully trained Forensic Evidence/HRD Dog will not disturb a crime scene nor will it retrieve evidence.  It will also search homes and vehicles without causing any damage.  When it finds a residual scent of a dead human or dried blood, for example, it will alert its handler by demonstrating a particular behaviour, such as standing still and barking, or lying down.

The scent may not indicate the actual location of the remains.  Running water can move the scent away from the grave site.  So although the dog will alert where the scent is strongest, this may be some distance from the body itself. 

The handler of a Forensic Evidence/HRD Dog also has to be highly trained.  If called to court, the handler has, in effect, to testify on behalf of their dog.  So handlers log all their dogs' training and also take courses in orienteering, criminal procedures, report writing, hazardous materials awareness and canine first aid.

So how accurate are Cadaver Dogs and Forensic Evidence/HRD Dogs?  Canine fallibility was alluded to in Deputy Forgey's cross-examination. 

Various studies have shown that handler error and inexperience can lower the recovery success rate from 100% to as little as 57%.  It doesn't matter how good the dog is at locating evidence, if the handler is unable to interpret the dog's alerts properly.

Just like a human, a tired, hungry or stressed dog will not perform as well as when it is fresh, fed and happy.  In fact, a severely fatigued dog may give a false alert, simply because it wants to rest.

Forensic Evidence/HRD Dogs are also employed away from law enforcement work. The Institute for Canine Forensics has been using Forensic Evidence/HRD Dogs to search for Native American burials and cremations on the site of the proposed Tule Wind Energy site in the McCain Valley, California.

Here is a video of one of the dogs at work.
       

Don't forget, you can find out when I post a new blog  - and much more - by following me on Twitter @forensicswrite.


 

The Body of Evidence

The English King, Richard III, was killed at the Battle of Bosworth on 22nd August 1485.  Contemporary accounts reveal that he was fighting heroically while pressed on all sides by his enemies, the armed forces of the rebel Henry Tudor (later Henry VII).  Famously (and possibly erroneously) depicted by Shakespeare as a murderous, unscrupulous monster, Richard III was the last English king to be killed in battle.  So why am I writing about a long-dead monarch in a forensics blog?  Keep reading to find out! 

 

An archaeological team from the University of Leicester, in association with Leicester City Council and the Richard III Society, has been excavating the site of a mediaeval Franciscan friary in Leicester called Grey Friars. 

On September 12th 2012, while excavating the choir of Grey Friars church, which is believed to be the burial place of Richard III, archaeologists discovered a grave containing human remains.

Could the remains be Richard III?  We shan’t know the answer, or even whether the question can be answered, until early in 2013.  But forensic science is playing a key part in the identification process.

Here is the link to the most recent article on the discovery, which outlines the scientific techniques being employed.  

The Science of the Search for Richard III

 

I imagine that the ‘ancient DNA’ technique being used is Mitochondrial DNA (mtDNA) analysis. Mitochondria (sing. Mitochondrion) are found in the cytoplasm of cells i.e. outside the nucleus.  They are one of the most important ‘organelles’ of a cell, since they are the site of the chemical reactions of respiration, whereby energy is generated for the needs of the cell.  A typical cell contains about a thousand mitochondria.

Old bones, badly decomposed or charred bodies are often poor sources of nuclear DNA, used in standard DNA profiling.  This is because the nuclear DNA becomes degraded, chemically modified or contaminated, and it is not possible to obtain a profile.  Mitochondrial DNA, although not immune to degradation, is better protected within the cell than nuclear DNA.  Its extreme abundance means there is a much greater chance of some of it surviving for longer.  

Human mtDNA is a circular molecule of DNA.  Most of it does not vary between individuals and therefore cannot be used as a forensic identification tool.  However, in a region of the molecule called the ‘D Loop’ or ‘Control Region’, variation does exist in DNA base sequences between unrelated individuals, which is of forensic value.    

I don’t plan to go into the minutiae of the technique here, but I will mention an important point about the inheritance of mtDNA. 

All brothers and sisters in a family will share the same mtDNA as their mother, but not their father.  They will also share the same mtDNA as their mother’s siblings and their grandmother.  This is because an individual inherits their mtDNA only from their mother.

As a consequence, mtDNA analysis cannot provide a unique identification because many individuals can have the same mtDNA base sequences.  Even between unrelated individuals, mtDNA analysis is not as discriminating as standard DNA profiling. The process itself is also not as straightforward as standard DNA profiling.  But it can generate data when standard DNA profiling fails, and this is the technique's undoubted advantage.

I’m very interested to discover that a (male) potential descendant of Richard III’s sister through the female line has been found, so that his mtDNA base sequences can be compared with the base sequences that, hopefully, will be obtained from the mtDNA of the remains.

It would be great if the scientific team are able to find sufficient evidence from their research to suggest that the remains are Richard III.  Follow me on Twitter @forensicswrite to find out.

 



A Question of Expertise

How many Forensic Scientists does it take to change a light bulb?  Answer: Two. One to screw it in and one to check for fingerprints.  Okay, it’s a pretty lame joke, but I’m using it to demonstrate that, in the real world, forensic scientists stick to their own area of expertise.

Each member of the forensic teams of CSI demonstrates proficiency in a wide range of disciplines.  There is seemingly no specialism beyond the scope of their expertise.  The use of such a multi-skilled cast of characters is partly a cost issue, of course.  However, engaging the viewer by re-visiting the characters week by week is a good way of developing loyalty to the show. 

In reality, of course, there is a clear demarcation between examinations carried out at the crime scene and those performed in the forensics laboratory.  Within the laboratory itself, a DNA specialist, for example, would not examine documents or perform toxicological analysis.  Each scientist keeps within their own discipline.

Crime scene investigators ‘read’ and reconstruct the events that took place immediately before, during and after the crime was committed.  They ascertain the type and location of the evidence and collect and package it correctly.  They document and photograph their actions throughout.  They also produce reports on their scene visits, which will form the basis of their expert testimony in court.

In the forensics laboratory, the scientists process the pieces of evidence collected by the scene investigator, whilst documenting all their actions in detail.  They too will produce reports on the results of their analyses, and may be summoned to appear in court as expert witnesses.

So you can see that the two roles are not interchangeable.  However, there is nothing to stop a scene investigator with a suitable science degree from moving into the forensics laboratory and training to become an expert in a single discipline.  They will already have a ‘feel’ for forensics, which can be a big advantage during the early stages of their new career.

Ultimately, it is up to you to decide what sort of forensics expert you want to create.  You could even invent an ‘expert’ who received his certificate of competence to practice from a diploma mill online! 

I’ll finish by wishing all my US readers a Happy Thanksgiving.  I hope you have a wonderful time.



Making an Impression

It is 1979.  A man walks into a bank, covers his face with a balaclava and hands the only cashier on duty a note and a carrier bag.  The note reads:  'I HAVE A GUN.  GIVE ME THE MONEY OR I WILL SHOOT YOU'.  The terrified cashier thrusts some notes into the carrier bag and hands it to the man.  He runs off, just as the cashier manages to activate the alarm..  In his haste to escape, he forgets to ask for the return of his demand note.  Two days later, he answers a knock at the door and discovers two police officers, who have come to arrest him for armed robbery.  He is so surprised that he confesses on the spot.

 

A police officer told me a version of these events many years ago.  The story may be apocryphal, but it serves to illustrate the major impact of a piece of newly operational forensic equipment, not only in solving cases of armed robbery, but also terrorism, murder, fraud and corruption, for example.  The existence of  ESDA (ElectroStatic Detection Apparatus) was not widely known amongst the criminal fraternity in its earliest days, but its use in  a widely reported case of police corruption ensured that its existence eventually became public knowledge.

 

So what is ESDA and what does it do?

 

According to Foster and Freeman, its manufacturers, ESDA is 'the leading technology for detecting indented writing on questioned documents'.  When you write on the top sheet of a pad of paper, the writing will leave indented impressions in the sheets underneath.  In my armed robbery story, indented impressions of the offender's address were found on the demand note.  Just how many sheets will bear impressions depends on the writing implement, the degree of pen pressure and the type of paper.  Writing made with a ballpoint pen with reasonably firm pressure on good quality paper may leave indented impressions on up to six underlying sheets.  On the majority of these underlying sheets, the impressions are not visible on the paper surface.  However, ESDA is such a sensitive technique, that it may be possible to visualise the impressions on all six sheets.

 

The equipment is very easy to operate.  Here is a video of a police officer developing indented impressions in documents from a murder case. 

 

 

 

 

ESDA works by creating an invisible electrostatic image of the indented writing onto the surface of a plastic film.  The impressions are visualised by pouring a mixture of glass beads and charge sensitive toner (like you find in photocopiers) over the surface, until the image is developed.  A permanent record of the image can be made by covering the surface with a sheet of adhesive transparent plastic. Known as an ESDA 'lift', the resultant transparency consists of the plastic film bearing the visualised indented impressions covered by the adhesive plastic.  The lift is trimmed to size and can be used to overlay writing which is suspected of having produced the impressions or simply read for information purposes.  If the impressions are of particularly good quality, they can form the basis of a forensic handwriting comparison with a suspect's writing.

 

A variety of information can be obtained from indented impressions.  If a page has been torn out of a diary, ESDA may be able to detect what was removed by examining the pages on either side.  In a murder case, where the victim knew her attacker, the victim had made a note in her diary that she would be meeting her attacker on this particular day.  Whilst checking that there was nothing to connect him with the crime, the murderer discovered the victim's diary.  He tore out the offending page and threw it away.  An ESDA examination of the pertinent pages of the victim's diary revealed the attacker's name.

 

A man committed suicide and left a bitter note for his wife.  She has destroyed the note because she feels she drove her husband to take his own life and cannot face his family.  Eventually, she tells the police that there was a note and it had been written on the pad by the telephone.  An ESDA examination of the top sheet of the pad would show exactly why her husband committed suicide and why she felt so guilty.

 

A suspect in a case of money laundering passed four handwritten receipts to the police, which, he stated, accounted for four large payments made into his business bank account.  The receipts covered a four month period between June and September 2007 and were dated at monthly intervals.  The police suspected that the receipts were false and had been created purely to legitimise the transactions.  Were the dates on the receipts genuine?

 

By using ESDA, it was discovered that there were indented impressions of the writing from the receipt dated in September 2007 on the receipts dated in August, July and June 2007.  There were also impressions of the August receipt on the July and June receipts and impressions of the July receipt on the June receipt.  This is clearly impossible if the receipts are dated correctly.  Undoubtedly, all the receipts had been written at one sitting and their dates were not genuine.

 

I'm sure you could think of many more examples where ESDA would be invaluable in helping to solve crimes.

 

A big bonus of the ESDA technique is that the document containing the impressions is not damaged in any way,  Furthermore, provided that the document has not been treated with fingerprint reagents, the technique still works after many years, and could, therefore, be of value in cold cases.

 

So when your characters decide to send a handwritten anonymous letter or plan an armed robbery on paper, they should take care what they leave behind!

Forensic Meteorology - more than Blue Sky Thinking

It was a dark and stormy night.  Okay, so no crime writer worthy of the name would ever begin a novel with such a tired sentence.  But in a murder investigation, detectives may need to establish that it was stormy on a particular night.  They may need to know when the storm started and what impact it had at ground level, for example. 

 

The investigating officers could consult weather reports and get an overview of the conditions in the area.  However, only a Forensic Meteorologist will be able to supply the precise details of the weather at the specific time and location pertinent to the investigation.

 

Forensic Meteorologists reconstruct weather conditions that occurred at a particular time and location, rather than predicting what the weather will be like.  Using a variety of archived data sources, including radar, satellite imagery, local weather station observations and National Weather Service bulletins, a Forensic Meteorologist will analyse the data and recreate a timeline of weather events for a certain location on the desired day.

 

Most of the work of a Forensic Meteorologist involves civil cases.  Did the person who broke their leg after a fall in the street, really slip on some ice or had the ice melted some hours before?  Did lightning really spark a fire which caused extensive damage to a house or did somebody fall asleep with a burning cigarette in their hand? 

 

Insurance companies are good clients of Forensic Meteorologists.  The roofing and engineering industries also have good reason to engage Forensic Meteorologists.  If a roof is allegedly damaged by hail, for example, a Forensic Meteorologist can provide a scientifically accurate report that will verify the presence or absence of hail at the address in question.

 

In criminal cases, a Forensic Meteorologist may be able to break a murderer's alibi.  In 2002, Michael Mosely was accused of bludgeoning two people to death in Troy, New York State.  When he was arrested, Mosely had a cut on his hand.  He claimed the cut was not suffered during the killings but happened while he was snowboarding with his son.  The DA's office in Rensselaer County, NY called in Howard Altschule, an experienced Forensic Meteorologist.

 

Mr Altschule testified that at the time Mosely said he was snowboarding, it was actually raining.  Using radar maps, Mr Altschule was able to show precisely where and when the rain was falling.  Although the rain was light, it was significant enough to melt any snow.  Mosely's alibi was destroyed.  The jury found him guilty of both murders.

 

In another criminal case, Howard Altschule's evidence was crucial in assisting the prosecution.  In 2009, Omar Long stood trial for the manslaughter of his daughter, Arianna, aged 23 months.  Long left Arianna in his car, so he could take a nap.  While he slept, Arianna died.  The cause of death was hyperthermia - extreme heat exhaustion; the post-mortem also revealed that she had second degree burns on her body.

 

Watch an interview with Howard Altschule, where he explains what happened to the temperature inside the car.

 

 

 

Long was found guilty of manslaughter by culpable negligence and sentenced to 12 years imprisonment.  He appealed unsuccessfully against his sentence earlier this year.

 

The field of forensic meteorology is growing fast, although its use in criminal cases is probably under-exploited at present.  I'm sure forensic meteorology could form the basis of some inventive plot lines.  Do you agree?

 

  

 

Bloodstain Removal - a Killer's Dilemma

‘Did you ever notice how they have commercials on TV with detergents that can get out bloodstains?  If you have blood all over your shirt, I don’t think laundry is your biggest problem’.  Jerry Seinfeld  

It is virtually impossible to remove bloodstains from a crime scene.  The assailant who has killed his victim in a kitchen or bathroom with easy to clean surfaces may feel confident that no trace of his crime remains.  However, tiny specks of blood can remain in the room and, crucially, may still be there many years after the killing. 

A particularly difficult cleaning problem confronts the assailant who has committed his murder surrounded by absorbent surfaces like carpets, curtains and bedding.  Cold water is probably the most effective way to remove bloodstains – to the naked eye, at least.  Hot water just fixes the stain and the use of chlorine-based bleach turns the bloodstain a pale green-brown.

Blood visualisation chemicals, such as the highly sensitive Bluestar®  Forensic reagent, can reveal the presence of bloodstains that have been wiped away, washed out, or are invisible to the naked eye.  The haemoglobin (an oxygen-carrying protein) in the blood reacts with the chemicals in the reagent to produce the glow-in-the-dark effect much beloved of television producers.  This process is known as chemiluminescence. 

But what if a substance existed that would remove haemoglobin? Bluestar® Forensic reagent cannot work without the presence of haemoglobin. 

I mentioned that chlorine–based bleach is ineffective at bloodstain removal.  However, there is another type of bleach found in some household cleaning products – including washing powder – that contain oxygen bleach.  Scientists at the University of Valencia in Spain have discovered that oxygen bleach removes haemoglobin.

Their tests showed that washing powders containing oxygen bleach will not only make bloodstains fade but they will also make them unreactive to blood visualisation chemicals, owing to the removal of the haemoglobin from the stain.

The killer’s dilemma now becomes the forensic scientist’s dilemma. Even if a stain is still visible, because it is unreactive, it will not automatically be tested for DNA, since it has not been verified as being of human origin.  This means that useful evidence may, potentially, be lost.

But, it takes only a drop of the victim’s blood on a suspect’s clothes to confirm that the suspect was at the scene at the time of the attack.  Blood embedded in the seams is very resistant to washing and can be easily missed in the assailant’s clean-up operation.

Cold cases heat up through new approach to identifying remains

Cold cases heat up through new approach to identifying remains

I found this article in Science Daily that I thought I would share with you.  It describes how a multidisciplinary approach allowed the legal identification of a person whose remains had been discovered 41 years previously.  I thought it was a very interesting article; I hope you like it too.

 

All my blog posts are designed to help you with forensics techniques and maybe provide you with a bit of plot inspiration at the same time.  My 'Scenes of Crime' newsletter is also designed for the same purpose. 

However, owing to a few production issues (aka my ineptitude!), future issues of 'Scenes of Crime' will be delivered as opt-in e-mails.  You will be able to sign-up to receive them in the next 2 or 3 weeks, and I'll do my very best to stick to a monthly schedule. 

Don't forget to send me your questions for 'Forensic Fix-it'.

DNA Debacle: the sequel

I’ve been busy with urgent casework these last few days, so my apologies for posting only once this week.

One of the news items that I highlighted in the June/July edition of Scenes of Crime concerned the case of Adam Scott, who was charged with rape based on DNA evidence, despite maintaining that he had never visited the city where the rape occurred.

LGC Forensics, the largest private forensics company in the UK, had recently introduced a robotic DNA extraction system at the time the rape case sample was processed.  An investigation revealed that a technician had incorrectly re-used some plastic trays, resulting in a contaminated profile.

Even before the contamination came to light, the investigating officer had expressed concerns about the DNA result.  An analysis of Adam Scott’s mobile phone records revealed that he was 300 miles away when the rape took place.  However, LGC Forensics initially refused to consider the possibility of contamination.

Charges against Mr Scott were eventually dropped, but not before he had spent 5 months in prison.

An independent report from the Forensic Regulator, whose task is to monitor the quality of procedures used in forensic science, found that Adam Scott was an ‘innocent victim of avoidable contamination’.  The report stated that LGC Forensics’ DNA rape sample procedures were ‘not adequate’, and disclosed poor record keeping by technicians and failure to follow procedures for the disposal of used plastic trays.

LGC Forensics was also criticised for not responding more fully to the discovery that the plastic trays were being re-used.  However, the Forensic Regulator conceded that the company had now taken corrective action to address the shortcomings in its contamination avoidance and checking procedures.  No other instances of contamination had occurred.  

This incident adds more fuel to the argument that the private sector is incapable of absorbing the caseload of the now defunct Forensic Science Service of England and Wales.  I don’t happen to share this view.  The private sector knows how to operate a forensic science business; the Forensic Science Service was never equipped to operate as a business.  Nevertheless, this was a regrettable and inexcusable incident of ‘human error’ and Adam Scott may well be suing for compensation.

Listen to Adam Scott's grandparents talking about the case.

Forensics for Art's Sake

I’m sure nobody becomes a forensic scientist expecting to be thrust into the limelight.  I’ve worked on many high profile cases in my career, but have generally stayed under the radar.  However, I was lucky enough to be asked to examine a signature on a painting, thought to be a missing work by the much-loved English artist J M W Turner.  As a result, I have had my 15 milliseconds of fame, to mis-quote Andy Warhol. 

The painting, entitled ‘Fishing Boats in a Stiff Breeze’ was bought at auction for £3700 ($5980).   It is signed ‘JMW Turner’ in dark brown paint; the year ‘1805’ is written after the signature in the same paint.    

After an initial OMG moment - if the signature was genuine, then the value of the painting was estimated to be of the order of £20 million ($32.4 million) - I realised I should treat this examination the same as any other forensic signature examination, although I would also have to research the handwriting styles of the period. 

My essential requirements were examples of Turner’s signature written around 1805, or within a few years either side; a sample of 10 signatures would be ideal. 

This is when I discovered that Turner only signed his paintings when he either sold them or gave them away as presents.  I had expected to use the large collection of Turner paintings in Tate, London, as my source material.  However, they had been bequeathed to the gallery after his death; not a single painting was signed.

To cut a long story short, I did not get my 10 examples of Turner’s signature, but I did get to handle (with gloves, of course) some of his sketchbooks, which were a good source of comparison material.  When you have been used to reading death threats, ‘poetry’ expressing feelings of violence or sexual depravity and other generally unpleasant things routinely encountered by forensic scientists, it was a real privilege to be involved in a project where the questioned signature was on a beautiful painting and where most of my comparison writings were contained in books of exquisite drawings.

Although I wasn’t able to examine as much reference material as I would have liked, I saw enough to form an opinion about the authorship of the signature and date on the painting. 

In the meantime, a pigment analysis of the painting had been carried out, and the brown paint used to write the signature and date was considered to be contemporary with the rest of the work.  Modern forgery could therefore be ruled out.

My opinion, in summary, was that on the balance of probabilities, it is more likely that Turner did sign and date the painting than that he did not. 

So, along with other experts, I had helped to authenticate a missing Turner painting.  Last week the news hit the press.

 Missing Turner Painting Resurfaces

On Wednesday night, we presented our findings to an invited audience from the art world.  Beforehand, some of us were interviewed for a local BBC news programme.  It was fun – not a word normally associated with forensics. 

Are you planning to give your forensics characters their OMG moment? 

If you walk this way - exploring Forensic Podiatry

The work of a podiatrist involves the assessment, diagnosis and treatment of foot and ankle conditions.  Podiatrists may also treat back, hip and knee pain that is related to the way a person stands or walks.

A number of podiatrists working in clinical practice or university research apply their knowledge to criminal investigations. 

Gait analysis is one of five main practice areas of Forensic Podiatry (the other practice areas are footwear analysis and identification, bare footprint analysis and identification, footprint sequencing and identification of individuals from podiatric records). 

Offenders who conceal their faces from street CCTV cameras in the vicinity of the crime scene have discovered that they can be identified by the way that they walk.

John Rigg’s DNA was found at the scene of a domestic burglary and he was arrested on suspicion of having committed the offence.  However, the police needed corroborative evidence, as a good lawyer could argue away the DNA finding at court (contamination), or at least muddy the waters. 

Detectives began trawling through CCTV footage in the neighbourhood of the burgled house. They noticed a man with a distinctive bow-legged gait walking towards the house, but they couldn’t see his face.  They called in Ian Linane, a Forensic Podiatrist.

Mr Linane compared images of the bow-legged walker from the CCTV footage with images of John Rigg, taken whilst he was walking through the custody area of the police station, after his arrest.

Watch the video here and listen to Ian Linane describing his findings.

 http://news.bbc.co.uk/player/nol/newsid_7340000/newsid_7343600/7343683.stm?bw=bb&mp=wm&news=1&bbcws=1

Here is the CCTV footage only.

 

 

John Rigg pleaded guilty to two burglaries and received a two year jail sentence.

Forensic Podiatry is a developing and increasingly useful tool in forensic science.  It is practised most widely (but not extensively) in Canada, the USA and the UK.



The Misinterpretation of Murder

Blood found at a crime scene can provide key information about the events that took place there.  However, the analysis and interpretation of the appearance and distribution of blood is a complex area; inevitably, mistakes will occur.

 

Here is a case from Canada, where the prosecution expert misinterpreted part of the blood spatter evidence in a murder investigation.  Although the man convicted of second degree murder was not exactly innocent, his murder conviction was overturned on appeal.

 

You can read about the case below.  The account is on page 28 of the pdf and contains photos of the body and the relevant blood spatter.

 

www.the-investigator.co.uk/files/December_09_Update_web.pdf

 

Disagreements between forensics experts can be a fruitful area for crime writers, although, of course, both sides of the argument need to be credible.  In this case, the prosecution expert, Mr Julien, does not appear to have done his best work. Why not?  Was he under a major time constraint?  Was he lacking in experience?  At the trial, it appears that the defence did not put up their own expert to challenge the prosecution's findings.  Maybe they appointed an expert who actually agreed with the prosecution expert and who, in consequence, was also at fault for misinterpreting the evidence.  What do you think?

 

The defence expert, Professor MacDonell, had to perform his forensic examinations at court.  As I know from experience, this is not ideal, but as he appears to have been given advance warning that he wasn't going to have access to a forensics laboratory, he came suitably equipped with a stereomicroscope and a camera.  No doubt he carried out his work in the presence of a bored junior prosecution lawyer or police officer, who would be tasked with ensuring that nothing untoward happened to the evidence!

 

The outcome of Professor MacDonell's examinations was that justice was served correctly - a plea of guilty to manslaughter.

 

Do you plan to use forensics fallibility in your writing?  Are you a fan of duelling experts?  I'd be really interested to know.

 

 

Rapid DNA Analysis - a potential plot spoiler?

In a case of murder or rape, a forensics laboratory can, in theory, generate a DNA profile from a crime scene sample in 8 hours.  In practice, though, a backlog of processing may have built up through heavy caseload, staff sickness or equipment problems.  Whilst it is still possible for urgent samples to be processed within 2 or 3 days, any delay is obviously frustrating for investigators.

In the UK, a technique called RapidDNA is being trialled by a number of police forces alongside more established methods.  Its USP is that a DNA profile can be generated in about an hour.  This could mean that a murder suspect is arrested before he has had a chance to get cleaned up or dispose of his weapon.  A burglar may be caught before he has had the chance to sell on his stolen goods.

The equipment is only the size of a piece of aircraft carry-on luggage and is just as portable.  Yet it can analyse up to 4 minute samples of body fluids or cellular material left at a crime scene and deliver a DNA profile that can be searched on the National DNA Database (the UK equivalent of CODIS) within an hour.  Apart from the rapidity of the analysis, there is no time lost in taking the sample to the forensics laboratory, because the equipment can come to the crime scene. 

 

However, the RapiDNA system does have a particular limitation.  Whilst it is useful for intelligence gathering and evidence screening, the DNA profiles generated using this technique are based upon fewer markers than a standard profile. 

Where there is a match between a crime scene RapiDNA profile and a profile on the National DNA Database (NDNAD), the chance of the RapiDNA profile also matching the DNA profile of some unknown and unrelated person is one in a million.  For court purposes, this is not sufficiently discriminating.  A standard DNA profile would have to be generated from the crime scene sample back at the forensics laboratory and another search carried out. 

A match between the crime scene standard profile and a profile on the NDNAD would have a discrimination of the order of one in a billion (i.e. a thousand million).  To put it another way, the probability that the crime scene standard profile also matches the profile of some unknown and unrelated person is of the order of one in a billion.  This statistic would provide compelling evidence in a criminal court.

 

I've seen suggestions that writers using RapiDNA in their storylines will spoil the enjoyment of their readers or viewers because the crime will be resolved too quickly.  In my opinion, this viewpoint is rather dismissive of writers' creativity.  If the technique becomes mainstream, I look forward to the inventive ways in which it will be incorporated into your writing.  What do you think?  Will RapiDNA spoil your plots?

 

Don't forget you can get plot ideas from my free newsletters here:

 

Scenes of Crime June 2012 

 

Scenes of Crime July/August 2012

Welcome to my Forensics Blog

If you are a published or aspiring crime or mystery writer, please make yourself at home.

The crime and mystery genre is enjoying unparalleled success, fuelled in no small measure by the public's unending fascination with forensics.  But what if you feel that your forensics knowledge isn't up to scratch and you're not sure where to go for reliable information?  Well, my blog is here to guide you through the forensics maze. 

I'm going to discuss the established techniques of forensics and also introduce you to some which may be less familiar to you.  At the same time, I'll try to make the technical detail more accessible, so that you will have the confidence to incorporate it into your writing.  Occasionally, I'll highlight research projects that show potential for future forensic applications.  In addition, I'll post comments on cases that I think will interest you and include useful snippets of information to underpin your characters' world.  My aim is to help you give your writing the authenticity that your readers will love.

I've also produced a free newsletter for you called 'Scenes of Crime', which I plan to issue every month.  Download the first two copies here.

Scenes of Crime June 2012

Scenes of Crime July/August 2012

Thanks for stopping by; I hope you'll come back often.  In the meantime, I wish you a successful life of fictional crime.