Bones of Contention

Traditionally, forensic anthropologists determine the biological sex of adult or adolescent skeletal remains by evaluating the size and shape of the pelvis.  If the pelvis is missing, features of the skull, such as the browridge and mandible, can be used instead.  Measuring the long bones e.g. the humerus is a much less accurate method for sex determination, but sometimes, this is as good as it gets

How a forensic anthropologist goes about solving the problem of sex determination is demonstrated in this video, produced by the National Forensic Science Technology Center.  It shows a seminar entitled 'The Determination of Biological Sex from the Human Skeleton'.  It isn't too technical and has plenty of visual aids.  It's just over 20 minutes long but it is a very good overview of the subject.

In the seminar, the accuracy rate for determining biological sex using a visual examination of the pelvis is given as 90-95%.  In 2010, researchers at North Carolina State University published a method of determining biological sex using 3-D imaging technology of the pelvis.  They claim a 98% accuracy rate, or better, using their technique.

An added benefit of the NCSU technique is the ability to determine biological sex from pelvic fragments.  The examination of fragments can be a major stumbling block with traditional methods.  Unless the sex determination indicators are present in the fragment, the examination may come to nothing.  The researchers from NCSU hope to have solved this problem. 

The researchers chose 20 'anatomical landmarks' which differentiate males from females on the os coxa or hip bone.  They measured these 'landmarks' using 3-D imaging technology.

So, to determine the sex of a skeleton from a fragment of pelvic bone, the forensic anthropologist uses a digitiser to create a 3-D map of the fragment and measures the relevant anatomical landmarks.  These measurements are then compared with the published measurements for the same landmarks to determine the sex.      

This type of quantifiable data holds up well in court.  Rather than the forensic anthropologist having to present an expert opinion, which can sometimes be difficult for juries to comprehend, he or she can present a set of figures.  This is tangible and should be more meaningful to a jury.

Here is a link to an article about the research:

New technique for determining the sex of skeletal remains

Last week, researchers from the University of Granada in Spain published details of a new imaging technique for identifying the age and sex of skeletal remains, using features of the pubis.  The pubis is one of the three bones of the os coxa (hip bone).  In adults and adolescents, the three bones are fused together.

Traditionally, forensic anthropologists have considered that the pubis was only useful for the identification of remains in the age range 20-40.  However, the researchers found that they obtained good results from bodies of people older than 50, particularly men.

This new method of age and sex determination essentially combines imaging techniques with statistical analysis.  It is reckoned to be state-of-the-art and user-friendly, with an accuracy rate of 95%.

You can read about it here:

New imaging technique for identifying the sex and age of a corpse

I hope you have found something in this blog that you can use in your writing.  Do let me know if there are any topics you would particularly like to know more about.  I'm also happy to answer your forensics questions.  Don't forget to follow me on Twitter @forensicswrite.

 

 

 

 

 

The Case of the Crushed Skull

On 7th June 1996, a tractor driver unearthed a human arm while ploughing a field at Little Abshot Farm, Hampshire, in the south of England. 

 

When the police arrived, they noticed a swarm of flies about 50m away from where the tractor driver had been forced to stop.  They had found the owner of the arm. 

The body was buried in a shallow grave and wrapped in a blue sleeping bag.  The hands had been placed in front of the body and held in place between the thighs with a knotted scarf.  The skull was badly damaged.  The only item of clothing on the body was a Pringle sweater.

The pathologist who performed the post-mortem concluded that death had occurred as a  result of the skull being struck by a blunt instrument.  However, the plough blade had caused a lot of damage to the skull and neck, so the possibility of death by strangulation could not be ruled out. 

Owing to the body being very badly decomposed, most identification features had disappeared.  The police knew that the body was male and that he had a gold crowned tooth.  No missing persons in Hampshire were a likely match. 

The body was too decayed for useful analysis of DNA or body fluids.  A toxicological analysis revealed no traces of drugs or poisons in the blood or other organs.  However, the results were not conclusive because of the level of decomposition. 

A gastroenterologist examined the body's stomach contents and found that the deceased's last meal was a vegetarian chilli with kidney beans.

When an odontologist examined the teeth, he discovered that they had a very low incidence of decay. This is typical of immigrants into the UK from the Indian sub-continent.  The degree of wear on the teeth indicated that the body was between 30 and 50 years old.  The gold crown contained only 21% gold instead of the usual 60%.  However, this did not turn out to be particularly unusual.  179 dental technicians were found to be using this lower quality metal in their work. 

A trichologist examined the hair and found it was naturally dark brown and not dyed.

Two fingerprints from one of the hands that had been tied between the thighs were able to be checked with immigration and national databases, but with no result.

There was no good news when the sleeping bag, jumper and scarf were examined.  The sleeping bag was the most common type available and the Pringle jumper was a fake.  The scarf was an Indian 'chunni', but at this point, its significance was unknown.  A forensic examination of the knot revealed nothing useful.

The police investigation team were left feeling frustrated with their lack of progress.

Then somebdy had the bright idea to commission a facial reconstruction.  Although the skull was severely damaged owing to the head injuries and the additional action of the plough, noted anatomical artist and forensic facial reconstruction expert, Richard Neave, was able to build up a clay likeness of the deceased. 

Here is a video which shows how facial reconstruction is done.

The image was used on the BBC programme 'Crimewatch', which asks for the public's help in solving crimes.  Within days of the programme being aired, the police had a name, Harjit Singh Luther aged 40 from Ilford, Essex.  The name and address of a possible suspect for Harjit's murder, Baljeet Rai from Southampton, was also put forward.   
 
The police attempted to formally identify Harjit from his dental records.  However, the records they were given did not match the deceased's teeth.  When the police queried this, a dental technician admitted using 21% gold for the gold crowned tooth but charged for 60% gold and pocketed the difference.  He had deliberately given the police the wrong set of dental records.  The right set of dental records confirmed the idenity of the deceasd as Harjit Singh Luther.

The suspect, Baljeet Rai, was an illegal immigrant from India, who had worked at Little Abshot Farm.  He had been refused political asylum and needed to arrange a marriage in order to stay in the UK.  He subsequently married Manjit Kaur, but she left him in February 1996 and returned to Harjit, by whom she had a daughter.  If his wife divorced him, Baljeet feared being deported to India. 

In 1998, both Baljeet and Manjit were put on trial for the murder of Harjit.  Manjit was acquitted, but Baljeet was sentenced to life imprisonment.  The judge recommended Baljeet's deportation.

So what happened?  In the early hours of a morning in April 1996, Baljeet entered Harjit and Manjit's flat in Ilford and found them in bed.  She woke up and was ordered to get out of bed and be quiet.  She grabbed her daughter and watched from the landing while Baljeet beat Harjit to death with a hockey stick.  At some point, Baljeet and Manjit drove the body to Little Abshot Farm in his Vauxhall Cavalier - a distance of about 100 miles -  where he buried the body in a heap of soil that had been brought onto the farm from a nearby irrigation canal.  He did not know that the heap would be flattened and the land used for planting, otherwise the body may have lain undiscovered for much longer.

This case was the largest murder investigation ever carried out by Hampshire Police. 14 different areas of expertise were called upon and around 3000 exhibits were documented, many of which were forensically examined.  But ultimately, it was a combination of the facial reconstruction and a lucky phone call that paved the way for solving the case of the crushed skull.






      



 

 



Seal of Approval for Crime Writers

In theory, it's possible to write a crime or mystery story without worrying too much about the technical details of the crime itself or the investigation that follows. However, if you make an obvious mistake, you run the risk of alienating your readers, some of whom will jump at the chance to contact you and set you straight!  My blog and those of D.P. Lyle and Tom Adair , for example, have been created to help you get the essential facts right.

But how will your readers know that your book is well researched and factually accurate?  What could persuade potential new readers to buy your books on this basis alone?  The Washington Academy of Sciences (WAS) may have the answer.  

Since June 2012, the WAS has been reviewing crime books for the accuracy of their science.  So far, they have awarded their seal of approval to four books; a fifth book is under consideration.

Here is a link to an article that discusses the award and the reasoning behind it.  You'll also find a list of the 'approved' books.

Seal of Approval for Crime Writers

Is it a good idea?  I think it is.  An awful lot of people are turned off by science at school, but love it when it is packaged in an entertaining way, such as in a crime novel or TV series.  This can be a double-eged sword.  The 'CSI effect' has become a much talked-about phenomenon. Many legal commentators have suggested that jurors have unrealistic expectations of forensic science as a result of watching the programme.  They fear that this could prejudice the outcome of a case at trial. 

Presumably, the WAS hopes that its scheme will go some way to rein in these expectations, although, in the short term, I doubt that the public's perception of forensic science will change significantly. . 

However, good idea or not, let's keep it in perspective.  The whole point of a crime novel or TV series is to entertain the reader or viewer.  Nobody reading for pleasure or watching TV for relaxation wants a text book or a lecture.  It's the way in which the (accurate) technical information is woven into the plot which will ultimately determine the writer's success.

Contact details for the WAS

Are you in favour of this scheme?  Why not leave a comment at the end of this blog.

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

My most recent tweets link to articles  discussing fictional murders on TV and identifying the dead from the contents of their pockets.  You'll also be the first to know when I've written a new blog post.

Getting Rid of the Evidence

Are the 'bad guys' ever desperate enough to launch a physical attack on a forensics laboratory that is holding evidence that incriminates them? 

 

Attacks on forensics laboratories are not unknown but, fortunately, their occurrence is rare. 

 

In 1976, during the Troubles in Northern Ireland, a 900kg explosive device reduced the forensic science laboratory in Belfast to rubble.  Valuable forensic evidence for use in the prosecution of terrorist suspects was destroyed.

 

On 18th February 2010, just after midnight, the Scottish Police Services Authority Forensic Science Laboratory in Edinburgh was firebombed.  The laboratory deals with about one-fifth of Scotland's forensics casework.  A masked man was spotted running away from the scene, before getting into a small, dark-coloured car.  The car, driven by a second man, sped off into the night.  Firefighters extinguished the two fires that had been started in ground floor offices, but there was extensive smoke damage throughout the building.

The firebombs did not cause any structural damage to the areas holding forensic exhibits (or 'productions', as they are called in Scotland), so the perpetrators may not have achieved their aim.  There was no report on whether the smoke damage had affected subsequent forensic examinations.

Here is a description of the two men thought to be responsible for the crime, but as far as I know, they have not been identified.

 

Description of alleged forensic laboratory firebombers

Away from man-made destruction, natural events, like Hurricanes Sandy and Katrina, have wreaked havoc on potential forensic evidence, with interesting consequences for the criminal justice system.

Here is an article from the New York Times about the Hurricane Sandy-induced flooding of two NYPD warehouses containing items awaiting forensic examination, what is happening in the courts as a result of 'inaccessible' evidence, and how the New Orleans Police Department is still struggling with forensic issues after Hurricane Katrina.

Flooding of two police warehouses destroys evidence needed for criminal trials

Don't forget you can follow me on Twitter @forensicswrite where I tweet links to articles about forensics or crime writing or perhaps both at the same time.  Please feel free to send me a forensics query or leave a comment on my blog.  I'd love to hear from you.



 

Character Witness

A sure-fire way to insult the profession of forensic handwriting examination is to refer to its practitioners as 'graphologists'.  Despite Freud's assertion that 'there is no doubt that men express their character through handwriting', science begs to differ.

 

Certainly, there is some confusion between the terms 'graphology' and 'forensic handwriting examination', particularly within the legal profession.  To make matters worse, a number of graphologists profess to practise forensic handwriting examination.

 

So, what is the difference between these two disciplines?  According to the British Institute of Graphologists, graphology is based on the principle that 'every individual's handwriting has a character of its own and this is entirely due to the uniqueness of the writer's personality'. 

By contrast, forensic handwriting examination is the application of scientific method and techniques to the comparison of handwriting and signatures for the purpose of assigning authorship.

 

A graphologist will analyse and interpret handwriting by means of in-depth psychological and personality investigation.  The services offered by graphologists include management selection, compatibility asessments, security checking and personality profiling.
 

Forensic handwriting experts are concerned with determining who has written or signed a document.  Disappointed relatives may allege that the testator's signature on a will is a forgery, when they did not receive an expected legacy from the deceased.  The police may discover a handwritten list of drug deals during a search of a suspect's house.  In the will example, the forensic handwriting expert will compare examples of the genuine signature of the testator with the disputed signature.  In the list of drug deals example, the suspect's handwriting will be compared with the handwriting of the list.  In both examples, the purpose of the examination is to determine authorship and not to establish the writer's state of mind or character.

Forensic handwriting experts are also forensic document examiners.  They will, therefore, possess expertise in other areas, such as the detection and interpretation of erasures, alterations and indented impressions, and the examination of printed and phocopied documents.  This work is outside the scope of graphology.

So, there is clear daylight between the two disciplines.  Now, I am prepared to be proved wrong here, but I do not know of any forensic document examiner who has a sideline in graphology or who has ever dipped a toe in the graphological water.  There are, however, a number of graphologists who do not recognise the distinction between the disciplines and have set themselves up as forensic handwriting experts, while still continuing to practise graphology.

Graphologists are, technically, handwriting experts, of course.  However, the term in its legal sense is a definition of those who give expert evidence in court.  As any lawyer will tell you, the purpose of expert evidence is to provide the court with information on scientific procedures or results that are outside the experience of judge and jury.  So the question here is whether graphologists can claim to have credible expertise in court, particularly as they may not be scientifically trained or possess any relevant qualifications.

The answer to that is a resounding 'No'.  There are many examples where graphologists who claim to be forensic handwriting experts have been discredited in the US Courts.  In one example, the testimony of a so-called expert witness was excluded on appeal because the individual practised graphotherapy in addition to forensic handwriting examination, was not a member of the American Board of Forensic Document Examiners and had obtained a Master's degree and Doctorate by correspondence.

Some graphologists try to side-step the expert testimony obstacle by offering a 'Signed Declaration' instead of appearing live in court.  In effect, they are refusing to attend court and put their 'expertise' on the line, something that no reputable forensic document examiner would ever do.

Forensic document examiners receive expert witness training during their probationary period and accept that attending court is part of their duties.  It will be obvious to the court that the forensic handwriting expert has the requisite scientific background and training to be called a 'handwriting expert' in the legal sense. Utimately, however, it is the Court's responsibility to establish competency.

The only way to become a bona-fide forensic handwriting expert is to undertake a professional apprenticeship.  This effectively bars the door to graphologists wishing to 'cross-train', but, undaunted, they are still out there.

As a crime writer, you could have a lot of fun setting up a courtroom battle between a forensic document examiner and a graphologist.  I'm still not sure what a 'limp 7' is, to quote from a graphologist's report of many years ago.

For now, I wish you a happy and prosperous 2013.  I hope your writing dreams will be fulfilled.