kbc@keithborer.co.uk +44 (0)191 332 4999
Home Services Our Team News FAQ Vacancies

Fingerprint Experts’ errors are in ‘No Doubt’

May 01 2015

Forensic Science Interpreting The Evidence

Related Services

Fingerprint Experts

Simon Bunter, one of our Fingerprint Experts, has had some interesting times challenging the certainty of fingerprint identifications in casework.  The day-to-day working practices of many Police Fingerprint Experts have changed very little in recent years, despite criticisms and recommendations from both the R-v-Smith Court of Appeal judgement and The Fingerprint Inquiry Scotland report, which means the strength of fingerprint evidence continues to be overstated in many cases.  Below are several examples where we have tested the ‘certainty’ of the Crown’s fingerprint identification and found it wanting.



In this case Mr Bunter questioned the Crown Fingerprint Expert’s ‘conclusive’ identification result.  His report highlighted how the Fingerprint Expert had contradicted himself when trying to indicate the position of supposedly ‘clear’ matching detail in the prints, and also how the same expert had originally failed to identify one of the prints, before changing his mind and being in “no doubt” as to its identification.  Upon scrutiny of the Fingerprint Bureau documentation, Mr Bunter noted that there had been an apparent attempt to erase the notes recording the expert’s original opinion.

After several Crown attempts at producing and presenting this key fingerprint evidence to the court, the Judge dismissed the case remarking that, in his opinion, the fingerprint evidence was weak.



A Police Fingerprint Expert provided written evidence that 16 ridge characteristics in a scene print matched the defendant’s partially taken thumb impression, obtained from him when he was charged with the offence.  The expert was in “no doubt” regarding this identification and it had been checked and confirmed by another three Police Fingerprint Experts from the same Bureau.

Mr Bunter was not happy with the partial reference prints the police had used and carried out his comparison against a set of the defendant’s complete fingerprints.  This comparison showed that there were several differences between the top of the mark and the tip of the defendant’s thumb.  These differences were only visible on the reference set of complete fingerprints that had not been used by the Police Expert in her evidence.

At court the Police Fingerprint Expert refused to accept that there were differences between the prints and would not re-examine her findings using the complete reference set.  Due to the difference of opinion, senior personnel from the Fingerprint Bureau decided to canvas opinion from two other Police Fingerprint Bureaux.  The results varied from ‘Inconclusive’ to ‘Identification’.  Due to the disparity of conclusions between the experts the CPS decided not to proceed with the case.



In this widely reported case, a poor quality fingerprint in blood was found on a door handle at a murder scene.  The Police Fingerprint Expert analysed this print and initially deemed that it contained ...insufficient detail for any worthwhile comparison to be made.”  He went on to explain that the mark was of such poor quality that it was not possible to eliminate millions of other people as having made the print.  After a suspect was charged, however, the Police Expert re-examined the mark and amended his opinion to being in “no doubt” that the mark had been made by the defendant’s left forefinger.

At the trial, the Police Fingerprint Expert plus two of his expert colleagues from the same bureau gave evidence that they were in “no doubt” that the mark was made by the defendant.  We disagreed and Mr Bunter explained to the court why the print could not be safely attributed to Mr Smith.  Mr Bunter went on to explain that he had never seen a Fingerprint Expert identify a print of such poor quality.  Despite the issues with the fingerprint evidence, the defendant was found guilty.

During the subsequent appeal, a further two independent Fingerprint Experts gave evidence disagreeing with the Crown Experts’ identification and the appeal was allowed.  In the appeal judgement, the Judges criticised the lack of notes, working practices, reports and presentation of the Police Fingerprint Experts, commenting that “No competent forensic scientist in other areas of forensic science these days would conduct an examination without keeping detailed notes of his examination and the reasons for his conclusions.”

After this judgement, the questioned prints were forwarded to a panel of Fingerprint Experts from another police force.  This panel also concluded that the prints did not match.  


If you have any questions regarding fingerprint evidence, please contact Mr Simon Bunter BSc(Hons), FFS at our Durham office on 0191 332 4999.

Subscribe to our mailing list