HL Deb 14 May 1996 vol 572 cc44-5WA
Lord Renton

asked Her Majesty's Government:

Whether they will report on the work of the Forensic Explosives Laboratory.

The Minister of State, Home Office (Baroness Blatch)

On 14th March 1996 explosives contamination was found in a centrifuge at the Forensic Explosives Laboratory which is part of the Defence Evaluation and Research Agency. The laboratory carried out a preliminary investigation and laid all the information before the Government in a formal report. A copy of that report has today been placed in the library.

The Forensic Explosives Laboratory's primary role is to provide scientific support to the police service and to provide expert witnesses for the Crown Prosecution Service in cases involving the criminal use of explosives. One of the services it provides involves the laboratory analysis of swab samples taken to determine the presence of explosives and the type involved. This "trace" analysis involves a range of procedures including the use in many cases of a centrifuge.

The explosives contamination involved a small amount, not more than 30 micrograms (that is 30 millionths of a gram), of the explosive RDS, one of the main components of the explosive Semtex. It was detected in a part of a laboratory centrifuge which was probably already contaminated on its arrival at the Forensic Explosives Laboratory in 1989. By normal standards the amount of explosive detected was tiny but nevertheless it should not have been there.

The centrifuge involved was immediately taken out of operational action on discovery of this contamination and the trace laboratory thoroughly cleaned. No incidence of contamination from the centrifuge could, therefore, occur from that point on.

There is a small theoretical possibility that any casework sample showing RDX traces may have been affected by the centrifuge contamination. Regular quality assurance tests undertaken by the laboratory have not revealed RDX traces at a level which would suggest that casework samples are likely to have been contaminated but this cannot be ruled out completely. This may call into question evidence submitted by the FEL in criminal cases involving RDX.

On present information there may be around a dozen such cases which resulted in convictions, but the identification of all relevant cases and assessment of the possible risk of contamination are matters on which my right honourable friend the Home Secretary wants independent advice. He has therefore decided that an immediate independent review of the casework and procedures at the Forensic Explosive Laboratory must take place. The terms of reference will require the reviewer:

  1. (1) to report on the general likelihood of contamination being spread from the centrifuge to samples in the laboratory;
  2. (2) to examine FEL papers on all cases in which RDX traces were found and a criminal conviction resulted and assess the likelihood of contamination;
  3. (3) to examine FEL procedures in the trace laboratory and make recommendations.

Professor Brian Caddy, Professor of Forensic Science at Strathclyde University, has agreed to undertake this review and will begin work shortly. He will report to my right honourable friend in the first instance but the results and recommendations of his review will be made public.

As soon as it is clear which cases involved an RDX trace and resulted in a conviction we will notify the representatives of those concerned.

Once the report has been completed my right honourable friend will decide what further action should be taken, particularly with regard to any concerns raised about the possible contamination of casework samples which subsequently resulted in criminal convictions. If appropriate, he will consider whether particular cases should be referred to the Court of Appeal.

From the information presently available to my right honourable friend it would appear that the risk of contamination is small, but in a matter of this sensitivity, he is determined to act only on the basis of the most rigorous and independent scientific assessments. We will keep the House fully informed of the outcome of that scrutiny and the measures which flow from it.