Forensic scientist raised concerns over exhibit contamination in Stephen Lawrence murder investigation in 1999, court told

Gary Dobson, aged 36, and David Norris, aged 35, deny murdering the teenager in 1993, saying new scientific evidence against them has been contaminated over the years.

A 1999 report by police who were compiling a review of the exhibits showed forensic scientist Adrian Wain had expressed concerns about contamination of clothing taken from Mr Lawrence's body and garments from the suspects.

The report referred to the "deterioration of the packaging" in which the exhibits had been kept - brown paper envelopes sealed with tape.

It said: "The original Sellotape seals used when the items were seized in 1993 have become so inefficient that, in Adrian Wain's view, in the event of alien blood cells being found on the suspects clothing in any subsequent examination, he'd be unable to rule out the possibility of contamination having occurred at the point of storage."

Gary Dobson's barrister Tim Roberts told the scientist: "That was in fact a reasonable concern of yours at this time."

Mr Wain, who carried out the original tests on the exhibits, replied: "Yes. Yes it was."

The court heard Mr Wain had raised a similar concern in a 2001 letter to officers reinvestigating the case.

In that letter he said he was "very reluctant" to carry out taping of Dobson's seized jacket for fibre evidence, citing his "concerns about possible contamination in this case".

Mr Wain told the jury: "I think I was aware that the items had been in and out of the laboratory.

"I didn't have control of them outside the laboratory. I didn't know whether they'd been in the same location outside the laboratory."

The scientist was also questioned by Mr Roberts over tapings taken of Dobson's clothes for which no dating had been recorded by him and his colleague.

Mr Roberts told him: "This is very far from in order."

Mr Wain replied: "It's a simple mistake. One mistake out of 18 years worth of work."

The trial continues.