DRUGS and alcohol tests relied upon in court cases in Wales and England and by local authorities when deciding whether to remove children from their parents may have been unreliable.

It has emerged a criminal investigation has begun into Manchester-based Trimega Laboratories, which went bust in April 2014, and its successor organisation Randox Testing Services, which carried out toxicology tests for drugs and alcohol, and data provided by the labs since 2010 is being treated as “potentially unreliable”.

It is believed more than 10,000 cases across the UK may have been affected.

In a statement Wales’ children and social care minister Huw Irranca-Davies said: “The Welsh Government recognises the seriousness of this issue and the potential impact on public confidence in the use of forensic science in the justice system.”

He added: “The number of Trimega’s customers, such as local authorities, individuals, legal representatives and employers, affected is unknown and it may never be possible to identify them all, due to the company’s poor record keeping practices.

“Samples from Trimega cannot be retested, because of the extremely limited chain of custody records and natural degradation over time of any remaining original samples.

“Not all samples tested by Trimega will have been subjected to manipulation by these individuals.”

All local authorities in Wales have been asked to review their case files in order to identify any cases in which tests carried out by Trimega may have impacted child protection decisions.

Anyone concerned the result of a family court hearing may have been affected should speak to Citizen’s Advice or visit gov.uk/guidance/forensic-toxicology-tests