Forensic Access Newsletter - "Benchmark"
July 2008
Forensic Aspects Of The Defence Of Ronald Castree
In October 1975, 11 year old Lesley Molseed, of Rochdale, was murdered. In 1976 Stefan Kiszco was convicted of her murder and sentenced to life imprisonment. However, the Appeal Court quashed Mr Kiszco’s conviction in 1982 and he was released from prison (Mr Kiszco died in 1993).
During a re-investigation of the case DNA evidence was discovered that led to Ronald Castree being charged, in November 2006, with Lesley’s murder. Castree’s lawyers, Switalski's Solicitors in Bradford, approached Forensic Access to undertake a review of the forensic evidence against Castree. The case against Castree was based on evidence that his DNA had been found on “tapelifts” taken from Lesley’s knickers, during the original forensic investigation (“tape lifts” are simply lengths of sticky tape run over an item, stuck on acetate sheets and then examined microscopically for evidence such as fibres, etc.).
The original investigation into Lesley’s death occurred over a decade before the advent of forensic DNA profiling. In the 1970s forensic biology focussed on techniques such as blood grouping, and the stringent precautions that are now commonplace in forensic laboratories were then non-existent. However, 31 years on, the prosecution case against Castree relied on the results of highly sensitive DNA techniques.
 As an experienced and well respected forensic scientist, Forensic Access’ Roger Robson was the ideal choice for leading this case. He had worked as a forensic biologist in the Forensic Science Service (FSS), during the 1970s and had a good understanding of the procedures employed at the time of the original investigation. Roger brought in Forensic Access’ Clare Stangoe, and a retired FSS senior biologist, Ted Kilner, to assist with the investigation.
Lesley’s clothing had all been destroyed, but the tapings, made as part of the original forensic investigation were still in existence – it was on one of these tapes that Castree’s DNA had been found. The original case files were also still in existence.
Our work started with a case conference involving the QC (Rodney Jameson) and the instructing solicitors from Switalski's. This important meeting enabled us to make a focussed and tailored forensic strategy for our work, allowing us to home in on the key forensic issues (and thereby saving time). Put simply, Roger and Clare had to try to understand how Castree’s DNA could have been transferred to Lesley’s clothing - was this due to direct contact between Lesley and Castree, or to contamination in the forensic laboratory?
Roger and Clare visited the FSS laboratory at Wetherby and scrutinised the original case files, procedures, protocols and methods used in the 1970s. They also examined photographs of the laboratory where the case had originally been examined. The key points that they discovered were as follows:
- All exhibits in the original investigation were examined in one laboratory.
- There were obviously no precautions taken against DNA contamination (for example, deep cleaning the lab, thorough cleaning of benches and equipment) or the isolation of exhibits and staff from one case to another, to avoid DNA transfer.
- The tapes, made from rolling sticky tape over a victim’s or suspect’s clothing in order to lift fibres, etc. (which would also lift traces of DNA) had been opened and closed several times during the investigation, thereby exposing them to potential contamination from other items in the laboratory, or traces of DNA on the bench, or elsewhere in the laboratory environment.
Ronald Castree had confessed to having sex with a lot of women in the 1970s. Could his DNA have been on clothing that was present in the Wetherby laboratory at the same time as Lesley’s clothing? Could Lesley’s clothing, or the tapings taken from them, have been contaminated by transfer of DNA, or was Castree’s DNA present on the items due to his direct contact with them at the time of the murder? These were the questions Roger and Clare had to assess, impartially and objectively. They produced a balanced critique of the forensic aspects with the aim of helping to ensure that the evidence presented was safe and robust.
Ronald Castree was found guilty of the murder of Lesley Molseed in November 2007.
< next article >
|
