Friday, March 18, 2011

Buccal Swabs, DNA and Phantoms



Viewers of shows such as CSI, Law & Order, Silent Witness and NCIS will know what a buccal swab is: a big cotton bud that is rubbed on the inside of someone’s cheek to obtain a DNA sample. It is pronounced “buckle”.

I was involved with buccak swabs recently in connection with one of my clients. The client having refused to allow such a swab to be taken, the Commonwealth DPP then sought a court order forcing such a sample to be provided. The sample was reluctantly given, placed into a sealed, chain of custody bag and sent away for forensic analysis. A little while later the Federal Police came back sheepishly and asked for another sample. Someone had placed a heavy object on the plastic bag, or had sat on the bag, or something, causing the seal to be broken and the word VOID to appear on the bag in large bold letters. Eventually the client consented to another smear with the swab.

Contemplating that over an idle moment, I wondered why the big cotton bud was called a buccal swab. Had it been invented by Dr Buccal? The reality is more prosaic: it comes from a Latin word meaning “pertaining to the cheek” and was first used in popular English literature in 1838.

There is an interesting case, known as the Phantom of Heilbonn, that dates from 1993 in Austria, France and Germany. From that year the DNA of an unknown female was detected at crime scenes in those countries, including at six murder scenes, one of the victims being a female police officer from Heilbronn, Germany. Between 1993 and March 2009 the woman’s DNA was detected at 40 crime scenes which ranged from murder to burglaries and robberies. The DNA was found on items ranging from a biscuit to a heroin syringe to a stolen car.

The woman’s DNA was found at the following crime scenes:
• on a cup after the killing of a 62-year-old woman on May 25–26, 1993 in Idar-Oberstein, Germany (the DNA was analysed in 2001)
• on a kitchen drawer after the killing of a 61-year-old man on March 21, 2001 in Freiburg, Germany
• on a syringe containing heroin in October 2001 in a wooded area near Gerolstein, Germany
• on the leftovers of a biscuit in a trailer that was forcefully opened on the night of October 24, 2001 in Budenheim, Germany
• on a toy pistol after the 2004 robbery of Vietnamese gemstone traders in Arbois, France
• on a projectile after a fight between two brothers on May 6, 2005 in Worms, Germany
• on a stone after a burglary on October 3, 2006 in Saarbrücken, Germany
• after a March 2007 burglary at an optometrist’s store in Gallneukirchen, Upper Austria
• after 20 burglaries and thefts of cars and motorbikes between 2003 and 2007 in Hesse, Baden-Württemberg and Saarland, Germany; Tyrol, Austria; and Upper Austria
• after a 22-year-old female police officer was fatally shot in Heilbronn and her 24-year-old male colleague suffered life-threatening injuries and fell into a coma. The weapons and handcuffs of the officers were stolen.
• on a car used to transport the bodies of three Georgians killed on January 30, 2008 in Heppenheim, Germany
• after a burglary on the night of March 22, 2008 in a disused public swimming pool in Niederstetten, Germany
• after four cases of home invasion in Quierschied (twice), Tholey and Riol, Germany in March and April 2008;
• after an apartment break-in in Oberstenfeld-Gronau during the night of April 9, 2008
• after the robbery of a woman on May 9, 2008 in a club house in Saarhölzbach
• in the car of an auxiliary nurse who was found dead at the end of October 2008 near Weinsberg, Germany

In January 2009, the reward for clues regarding the whereabouts of the person was increased to 300,000 Euros.

No stone had been left unturned in the hunt for the Phantom, also known as “The Woman Without a Face”. Profilers had been called in from all over Europe and the police even consulted fortune tellers, diviners and psychics.  Enormous publicity and media attention was given to the search with numerous psychiatrists, profilers, detectives (amateur and professional) and crime reporters volunteering analyses, opiniions and information.

In March 2009 investigators discovered the same DNA on the burned body of a male asylum-seeker in France. Now this presented something of an anomaly: the corpse was male but the DNA was of a female. The investigators checked again using swabs from a different manufacturer and this time found none of the Phantom’s DNA. Realisation began to dawn on Europe’s finest: perhaps it was the testing procedure that was flawed.

Further investigation revealed that the cotton swabs used by police departments throughout Europe were found to have been contaminated before shipping. The DNA was in the very cotton swabs which were used to test for the presence of DNA.  The swabs had all come from the same factory and had been contaminated prior to shipping

Cotton swabs are sterilised before being used to collect DNA samples, but while sterilising removes bacteria, viruses and fungi, it does not destroy DNA.

According to an investigator:
"The things were double-packaged; we thought they were the Mercedes of cotton swabs."
According to Stefan König of the Berlin Association of Lawyers:
 "DNA analysis is a perfect tool for identifying traces. What we need to avoid is the assumption that the producer of the traces is automatically the culprit. Judges tend to be so blinded by the shiny, seemingly perfect evidence of DNA traces that they sometimes ignore the whole picture. DNA evidence on a crime scene says nothing about how it got there. There is good reason for not permitting convictions on the basis of DNA circumstantial evidence alone."
According to a headline in Germany’s Bild newspaper after the flawed testing was revealed:
"Are the heads of our police stuffed with cotton wool?"
Footnote:
I have previously posted an article on the fabricating of DNA evidence. It can be read at:


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