“You get called biased, in the police's pay.”
- Forensic scientist Lindsay Lennen, quoted in The Guardian, 17th January 2012
As Sandra Lean has pointed out (“No Smoke”, 2008, p. 163), there is no formal legal requirement for forensic scientists, blood splatter analysts, stomach archeologists etc. In principle a QC can call anyone to testify as an expert witness, and it is up to the opposing Counsel to attempt to discredit the witness. Only pathologists are required to have their credentials legally attested before they can give evidence in court.
Dr. James Walker
|The bedroom of the basement flat shared by|
Joanna Yeates and Greg Reardon, where he
alleged her earrings were found
|Joanna Yeates’s bathroom at 44 Canynge Road|
after forensic scientists had been at work on it.
Vincent Tabak did not mention the bathroom
in his testimony. Were the forensics technicians
told to eliminate potentially incriminating traces?
Although the protracted forensic examination of the house was well publicised in the media at the time, it was not even mentioned once during the trial. The only whiff the jury got of this part of the investigation was the conspicuous sight of chemical residues on the walls that met their eye when they entered Joanna’s bathroom during their field visit to Canynge Road. The bathroom was the only room in the flat that Vincent Tabak did NOT mention in his testimony of his alleged encounter with her. On 4 January 2011, SWNS published a photo of two people with breathing apparatus wearing protective overalls outside her flat, with a police warning sign in the foreground, “DO NOT ENTER – Dangerous chemicals”. The journalist explained that it is common to search a crime-scene for traces that have been “hyper-cleaned”, but the case against Vincent Tabak was made possible only because this intelligent man had apparently made no efforts whatsoever to cover his tracks. Was this effort just for show, or were the people in overalls engaged in eliminating any possible traces that could reveal the presence in the flat of the persons seen and heard by the landlord? Neither Ninhydrin, which the article mentioned, nor other scene-of-crime chemicals, are normally considered especially dangerous.
Joanna’s front door
|The removal of Joanna’s front-door|
The DNA evidence that was not further tested
|Forensic scientist Lindsay Lennen|
It started as a missing person inquiry, explained Henley in his article. The team from LGC Forensics started by examining items from Joanna’s home, looking for foreign DNA. After Joanna Yeates’ body was found on Christmas day, a colleague of Ms Lennen’s went down to Bristol to supervise the removal of Jo’s clothing and preserve any body fluids. “The body was frozen, so that was quite tricky.” Under the media glare, explained Ms Lennen, the work was flat-out: clothing, swabs, suspect’s clothing, all analysed and turned round in 48 hours.
|Journalist Jon Henley|
The “rapist” with the 190 mile alibi
|A person outside Bristol Crown|
Court on 18th October 2011
believed to be Tania Nickson
An incorrect match of forensic profiles, as in this example, is known as a “false positive” (How the Probability of a False Positive Affects the Value of
DNA Evidence, Thompson, Taroni & Aitken, J Forensic Sci, Jan. 2003, Vol. 48, No. 1
Paper ID JFS2001171_481)
The scientists who went to Longwood Lane
Dr. Karl Harrison
The jury at the trial of Vincent Tabak heard evidence from two scene-going forensic scientists whose presence in Longwood Lane had been requested by the police after Joanna Yeates’s body had been found. Tania Nickson testified in person, and it may also have been she who read out the statement from ecologist Dr. Karl Harrison, who is also described as a forensic archaeologist. Tania Nickson’s professional qualifications are unclear, as is her relationship to LGC Forensics at the time of this investigation. She seems to have subsequently become a member of the staff of the School of Defence & Security, Cranfield University, Shrivenham. There is strong support for the proposition that she did not attend the crime scene until Boxing Day. If this were the case, then she could not have seen the body itself lying on the grass verge of Longwood Lane. Nor could she know with any certainty that the blood that she took from the wall and determined was Joanna Yeates’s blood had not been collected from the victim’s nose and smeared on to the wall for the purpose of falsifying the evidence. It is unclear whether Dr. Harrison, who was Lead Scientist in the Ecology Team at LGC Forensics at the time of Joanna Yeates’s death (and who subsequently became Lecturer in Forensic Archeology at Cranfield University), arrived at the scene in time to see her body before it was moved. His statement implies that he did, but it cannot be ruled out that the materials he analysed were the leaves and snow that he had been told lay underneath, over and around the body.
|Flowers in Longwood Lane after it was re-opened. A patch of wall and|
three stones on top of it have been lightened, to make us think that this
is where stains of Joanna’s blood were found, and that the verge below
is where her body was dumped.
|Who was this mystery woman captured on video by ITN|
leaving Longwood Lane on Christmas day 2010?
Was she a forensic scientist?
Or was she Rebecca Birch, whose dog found the body?
Who were these other suspects?Jon Henley’s article in The Guardian marks the first time anyone connected to Operation Braid had publicly indicated that the police had any suspects as early as 48 hours after the body was found. Who could they be? Joanna’s work colleagues Darragh Bellew, Elizabeth Chandler and Michael Brown knew that Joanna was expecting to be alone on the evening she disappeared. Her best friend Rebecca Scott knew about Joanna’s movements, and might have been much closer to Clifton than she claimed. Colleague Samuel Huscroft, brother’s friend Matthew Wood, or Peter Lindsell could have made their way to Clifton after receiving her text messages. Neighbour Peter Stanley was at home for at least part of the evening and knew that Joanna’s boyfriend was going away.
The landlord and the blackmail
|Joanna Yeates’s landlord|
|The Chrysler Neon that Christopher Jefferies had been|
car-sitting for a friend, about to be taken away from
44 Canynge Road to be forensically examined
The saliva on her body
- On 11th and 12th January 2011, The Sun ran an exclusive story from unidentified police sources about DNA samples allegedly from the killer’s saliva on Joanna’s body.
- On 13th January 2011, The Mail carried a story predicting a breakthrough from DNA from saliva found on Joanna’s body.
- On 16th January 2011, The Mirror carried a story linking LGC Forensics to the murder in 1992 of Rachel Nickell and the firm’s involvement in the Joanna Yeates case. Dr. James Walker was identified as the scientist in charge of the firm’s DNA team. Unattributed statements claim that results of DNA swabs from the body were expected within days, but could be used only after an arrest.
- On 16th January 2011, The Sunday Express carried a report claiming that a tiny sample of DNA had been found on Joanna’s lips.
- On 17th January 2011 The Mail carried a story predicting a breakthrough from ‘partial’ DNA on Joanna’s body and giving their source as LGC Forensics.
- On 19th January 2011, 25 days after Joanna’s body had been found (and the day before Vincent Tabak’s arrest), the police leaked to The Sun newspaper a claim that they had made “a major breakthrough” in their search for the killer. This claim, and references to it in other media, were subsequently removed from the internet. It referred to the “enhanced DNA” match with which he would be confronted on the second day of his interrogation.
- On 21st January 2011, The Sun announced: “Mild-mannered architect Vincent Tabak, 32, was arrested on suspicion of murder yesterday… DNA traces were found underneath Jo Yeates’s clothing, police sources revealed yesterday — suggesting for the first time that she may have been sexually assaulted. Samples were found on the 25-year-old’s breasts, midriff and jeans.
Leaked from the laboratory for “financial gain”After Vincent Tabak had been arrested, on 20th January 2011, he was probably told that the police had received an anonymous tip-off from a “sobbing girl” who had telephoned in response to the televised appeal from Joanna’s parents. It was probably not until his second day in police custody that he and his solicitor were confronted with the detectives’ claim that a match had been found between the DNA profile derived from the saliva swab taken from him after his arrest and DNA found on Joanna’s body. The second statement that he and the duty solicitor prepared and submitted to the police said he had “no knowledge” of how the DNA match obtained from Miss Yeates’s body and clothing, which had been the grounds for arresting him, could have been his, and he disputed that it was his DNA at all. In this statement, he further suggested that this “evidence” might have been leaked to the press from the laboratory for “financial gain”. This probably refers to the report published in The Mail on 3rd January 2011 and the succession of other unattributed reports published in the media during the intervening weeks.
The match was fakedIf the enhanced DNA from the body matched Vincent Tabak’s DNA but not Christopher Jefferies’s DNA, that would have been a very good reason for police not to arrest the landlord, nor to wait nearly three weeks (with the aggressive national media growing increasingly critical and impatient) until 20th January 2011 to arrest Vincent Tabak. The fact that they did both these things indicates that the match obtained by analysing the unidentified body fluid on Joanna’s body was fake, contrived in the secure knowledge that it would be safe to do so, because the police were planning to trick Vincent Tabak into standing trial for a manslaughter plea entered by an imposter anyway. As Lindsay Lennen herself so pointedly stated to Jon Henley, the existence of the “confession” meant that the DNA evidence would not be subject to further testing. In other words, her forensic evidence was dependent on an unsound plea.
Why did they wait three weeks?
|Detective Chief Inspector Phil Jones|
The February 2012 issue of Police magazine included an article by journalist Tina Orr Monro based on an interview with Lindsay Lennen, who made this excuse for the huge delay in analysing the samples taken from Joanna’s body: “The DNA appeared to have either degraded or to have been inhibited. One theory put forward by the DNA unit was that there may have been high levels of salt in the snow, which might have inhibited the DNA. A high salt level might have resulted from the gritters, but this was not known. We cannot say for definite, but it could have accounted for the issues we had surrounding the profile,” says Lindsay.
Tina Orr Monro
Amazon Author Central)
“The focus group was quite specific to this case and it worked very well as it meant the different scientists could come together and share their findings. Everyone was aware of what was happening in the case even in areas outside their own specialism,” says Lindsay.
“Then, 25 days after the discovery of Jo Yeates’ body, scientists made a breakthrough. They found DNA matching Vincent Tabak on one of the samples recovered from her body. After two days of questioning, Tabak was charged on 22 January 2011 with Jo’s murder,” wrote Tina Orr Monro in Police magazine. The arrests of both Christopher Jefferies and Vincent Tabak fell on Thursdays, which lends support to the proposition that both were planned well in advance, probably in relationship to the magistrates. Vincent Tabak was charged, furthermore, just 28 days after the recovery of Joanna’s body. Delaying his charge any longer would have obliged the police to submit to a peer review by a senior officer from another force. So the timing of the TV appeal on 17th January by Joanna’s parents, which precipitated the alleged anonymous tip-off from a “sobbing girl”, must also have been timed to suit the timetable for Vincent Tabak’s arrest. The “sobbing girl” was never even mentioned at the trial, so she must have been invented for the purpose. The timing of the “breakthrough” in the enhancement of the DNA alleged to have been made on the 25th day must therefore also have been planned before the parents’ TV appeal, lending additional support to the proposition that the DNA on the body was contrived, and that it would never have survived being tested in court.
The wool fibres from the black coat
|Vincent Tabak in Asda wearing his black coat.|
The time display from the supermarket’s CCTV
at the lower left-hand corner of the recording
has been blurred out.
Lindsay Lennen in the witness stand
|Body fluids and DNA specialist|
Lindsay Lennen leaving Bristol Crown Court
on 18th October 2011 with an unidentified man
She claimed that the partial DNA profile obtained from the sample taken from Joanna Yeates’s chest was from two people. It was a million times more likely to be from JoannaYeates and Vincent Tabak than from Joanna and another person.
Vincent Tabak’s and another unidentified person’s partial DNA was also found on Joanna Yeates’s jeans – behind her knees – she alleged. She claimed that the DNA could have been transferred by touch or even breath, and this would have been consistent with Vincent Tabak’s carrying her body.
Lindsay Lennen asserted that the statistical interpretation of the results from Joanna Yeates’s jeans showed that it was 1,100 times more likely that this DNA was from Vincent Tabak and another person, rather than two unknown people unrelated to the defendant.
|The boot of the Renault Megane registered to|
Tanja Morson and used by Vincent Tabak
The witness told the court that there were blood stains on the sole and toe of Joanna Yeates’s sock and on her finger nails. Her blood was found on her pink T-shirt and lilac bra, as well as on the sole of the toe of the one thick grey sock she was wearing on her left foot. (According to This Bristol, 19th October 2011, the sock belonged to Joanna’s boyfriend Greg Reardon.)
Lindsay Lennen also confirmed that Joanna Yeates’s DNA was recovered from minute traces of blood found in the boot of the Renault Megane car belonging to his girlfriend that Vincent Tabak was driving on the night Joanna disappeared. Ms Lennen claimed that there was less than one in one billion chance that this was not Joanna’s blood.
Counsel for the Defence cross-examines Lindsay Lennen
|William Clegg QC|
Mr. Clegg explained to the jury that scientists could not say whether blood traces in the boot were the result of direct contact.
He asked Lindsay Lennen if Vincent Tabak’s DNA could have been transferred to Joanna Yeates if he had used a cycle bag to take her body from her flat in Canynge Road, Clifton, to Longwood Lane. She said that it may well have done, as the cycle bag would contain his DNA.
Mr Clegg asked: “What if we knew the body would have been placed in a cover that you would put a bicycle in? If the cover was done up that would prevent the transfer of DNA, unless DNA got on the cover of the cycle bag?”
Miss Lennon said: “Either that, or the blood was sufficient enough to seep through the cycle bag.”
Mr Clegg asked: “If at Longwood Lane the body was taken out of the cycle bag and the cycle bag put back in the boot, any blood transfer onto the bicycle bag either directly from Miss Yeates or the hands of Vincent Tabak would be a candidate for the DNA in the boot?”
Miss Lennon replied: “Yes it could be.”
Mr Clegg continued: “If a cycle bag was used to transfer the body from Canynge Road to Longwood Lane and that the cycle bag had previously been used to store the bicycle of Vincent Tabak then it may well be that the cycle bag itself would contain DNA from him, which in turn could be transferred to Miss Yeates – if he had her in that bag?”
Miss Lennon told him: “Yes that is possible.”
Mr Clegg also speculated that DNA on Miss Yeates’s body and jeans could have been from Vincent Tabak’s attempt to put the body over a wall.
Lindsay Lennen replied that it could not be discounted.
|44 Canynge Road, where the jury|
was told that Joanna was killed.
LGC Forensics were paid £83,379
but found no evidence in the
house to support this.
|Joanna Yeates’s boyfriend|
outside Bristol Crown Court
on 17th October 2011
Steve Allen boasts about this forensic “success”
Managing Director of
LGC Forensics 2007 to 1013
The limitations of “low copy number” DNA“Enhancement” of DNA is similar to (and open to the same objections as) the “amplification” process used for what some scientists call “low copy number” DNA – or in other words, blowing it up to infinity until it matches somebody. If you can get one brick in a wall to match, then bingo! – your wall matches your man with the single brick. Another way to look at it is to claim that you won the National Lottery, just because you got one of the numbers right out of six. You can certainly say that you got a match, but it is an “enhanced” match and a cop-out. For DNA to be conclusive, it must be a full profile taken from saliva, blood, hair, skin or flesh, or semen, or other bodily parts or extracts. In murder cases there is always exchange of bodily fluids or human hairs etc, whether pubic or head hair. Clearly, to find only a brick in the wall of a tiny particle of, let’s say saliva, is not credible, because, if investigators were to find any saliva trace of the killer, it would be a lick or cough or a splatter effect that would deposit a significant amount of DNA that would be capable of yielding a result. Finding the tail-end of alleged DNA is grasping at straws that are simply not there. Partial or enhanced DNA is not DNA, period. In other words, you couldn’t draw conclusions on the basis on alleged partial DNA – except of course to back up the stitch-up of a scapegoat and pretend that you have DNA.
The most obvious use of DNA analysis is for paternity tests, where you have two willing people trying to see if their DNA matches. Your children and your grandchildren would have conclusive matches with your DNA.
A private company specializing in DNA testing for forensic purposes has a strong commercial interest in encouraging politicians and detectives to test the DNA of as many potential suspects as possible. After Joanna Yeates’s landlord Christopher Jefferies was released, there was a call from Kerry McCarthy, the Labour MP for Bristol East, for all the men in Bristol to be DNA tested.
A company such as LGC Forensics has a vested interest in promoting the use of DNA as evidence. Had DCI Phil Jones made Joanna Yeates’s boyfriend a suspect, there would have been no need for any DNA testing, and LGC Forensics would not have received any publicity. DCI Phil Jones chose, however, to make Operation Braid an “A+ murder investigation”, concentrating his 70 detectives on unlikely suspects. Vincent Tabak was arrested and charged almost entirely on the basis of evidence obtained by enhancing DNA. His conviction provided LGC Forensics, as we have seen, with high-profile publicity at home and overseas to promote their DNASenCE process. It will not look so good for the firm when Vincent Tabak’s innocence is formally established.
|Joanna Yeates with|
her kitten Bernard
The real killer of Joanna Yeates would have had the opportunity to smear samples of her blood from his clothes inside the boots of other cars parked at 44 Canynge Road, especially those he found unlocked, to incriminate their owners. The fact that Vincent Tabak, whom the police and the CPS depicted as so cool and calculating, did not do this, suggests that he was not the real killer. Since they acknowledged that Vincent Tabak was clever and cunning, he would certainly have been clever enough to have avoided leaving DNA traces if he really had killed and dumped Joanna Yeates.