The mass review of 10,000 criminal cases because of concerns over forensic evidence is shocking – it’s the biggest recall of samples in British criminal justice history. But it comes as little surprise to our union.

Forensic data handled by Randox Testing’s laboratory in Manchester is being questioned as it may have been manipulated.

The implications of this mass recall are wide-ranging. The data in question includes evidence used in sex cases, violent crimes, driving cases and unexplained deaths across England and Wales.

This is about public trust in the criminal justice system. Without confidence in forensics – the fundamental evidence prosecutors rely on – convictions are open to serious scrutiny. The potential human impact could be devastating, both for victims and for people who are wrongly convicted.

Since 2010, when proposals to close the Forensic Science Service – the publicly owned organisation that provided forensic analysis to the police – were first floated, professionals working in forensics, including many members of our union, have warned that it could lead to miscarriages of justice.

Prospect members were shocked by the closure of the service. There were huge concerns about the wider implications, including the loss of experienced forensic scientists, the loss of impartiality of forensic evidence – and concerns that the private market lacked the capacity to deal with demand. The latest developments highlight what all those issues mean in reality.

There is clear evidence elsewhere that the private market isn’t working. The UK’s largest provider of forensics, LGC, recently sold its forensics security division to European company Eurofins, and there are rumours of other providers also looking to get out of the industry.

Prospect has consistently warned that the pressure to provide services and deliver profit is a hard balance to strike. Forensics requires maintaining high levels of control, which is expensive. Individual private companies dealing with commercial demands can lose sight of why they are doing this work: they are delivering an essential part of the criminal justice system.

There are already more reports emerging of child protection and family cases being affected by potential forensic manipulation.

As well as the truly scary implications for individuals in the criminal justice system, this is one of the clearest examples of the damage of privatising public services. Rather than overlooking this and taking it as an isolated incident, the government must pay attention. This is a symptom of a sustained attack on public services.

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