The Crown Prosecution Service says it will no longer use a lip-reading expert after she was accused of misleading a court about her qualifications.
Profoundly deaf Jessica Rees has been involved in more than 700 criminal trials using forensic lip reading techniques to analyse silent CCTV or police tapes, BBC2's Newsnight programme revealed. She has worked both for defence and prosecution lawyers.
Following a review of her role as an expert witness in prosecution cases, a CPS spokeswoman said: "The CPS has decided not to rely on Jessica Rees as a prosecution witness in current or future cases.
"As a precaution, the Crown Prosecution Service is contacting defendants or their representatives in those cases where Jessica Rees gave evidence for the prosecution and which resulted in a conviction.
"They will be provided with a disclosure package to enable them to advise their clients."
Ms Rees' credibility was challenged in a case at Snaresbrook Crown Court in London last year.
Defence barrister Edward Henry accused her of misleading the court in a CV which suggested she had a degree from Balliol College, Oxford. Ms Rees readily accepted she had not completed her degree and said her CV was meant to show only that she had finished the first two years of the course.
Ms Rees told Newsnight her evidence was highly reliable. She said: "I have to be very confident indeed to include any words in the transcript. And this only happens after an exhaustive process, which involves looking at sections of tape 40, 50, 60 times."
The CPS spokeswoman said that if lip-reading evidence was admitted to court, the judge will warn the jury of its "limitations" and the "possible risk of error".