A new forensic science scandal has hit the criminal justice system with 33 cases involving rapes and serious crimes being urgently reviewed to see if the convictions of those jailed are safe.

The new crisis revolves around a scientist with the Metropolitan police who has been suspended following concerns about their work.

Under review are 33 cases dating from 2012-17 including 21 rapes and sexual assaults and 12 cases involving other serious violence, drug offences and burglary.

A Met police spokesperson said it was believed that the cases the scientist had worked on had resulted in convictions. A key question will be how crucial her work was in convincing juries of guilt.

The member of staff from Scotland Yard’s forensic services is alleged to have failed in carrying out tests and to have wrongly informed investigators about how her work was progressing, police said.



The forensic scientist was suspended on 26 March as part of the investigation. It concerns forensic samples submitted as part of criminal investigations being carried out by detectives.

The Met said: “We are urgently conducting a review to understand whether there is any risk to the criminal justice process and to take remedial action where necessary.”

Forensics are the cornerstone of the criminal justice system, crucial to investigators and the courts in determining guilt or innocence, and what to investigate.

It is the latest instance of concern being raised about the integrity of forensics in the criminal justice system. In England and Wales 10,000 criminal cases are being reviewed after it emerged last year that data at the Randox forensic laboratory in Manchester may have been manipulated, resulting in the biggest recall of samples in British criminal justice history.

The regulator said this year that falling standards of forensic science, including the outsourcing of work to unlicensed private labs, was making miscarriages of justice inevitable.

In the case involving the Met scientist, it is understood that analysis of some samples relating to crimes was not carried out.

The urgent review will look at whether the forensic results worked on by the scientist can still be relied upon. If not, the review will examine how important those forensic results were in securing any conviction.

The Met said: “All victims in the affected cases have been contacted, where it has been deemed appropriate to do so.

“In the case of the investigations into rape and sexual assaults, victims have been contacted by a sexual offences investigative techniques officer.”

The case has been referred to the Forensic Science Regulator and the Crown Prosecution Service is also involved to help assess how significant the forensic evidence was in securing convictions.

Gillian Tully, the forensic science regulator, said she could not discuss the specifics of the case while the investigation was ongoing. “It is imperative that all staff working in forensic science understand the importance and impact of their work in the criminal justice system, the importance of quality standards and the provision of robust science,” she said.

“There is a robust system of regular checks and quality systems in place to reduce the risk of malpractice and, if it does occur, ensure it is detected and dealt with.”