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.