Criminal trials could collapse because of a potential failure to supply courts with DNA and scientific evidence following spending cuts and the Government’s troubled privatisation of forensic science services, a new report by the spending watchdog reveals today.

Spending on costly forensic examinations has been cut by more than £20m in the past two years and experts warned of possible miscarriages of justice as police save money by carrying out work within their own laboratories.

The research was ordered because of concerns about the closure of the independent state-run Forensic Science Service (FSS) in 2012 amid multimillion-pound annual losses and a series of blunders, which has moved the burden of testing on to police forces and the private sector. But cuts in spending on forensic science have prompted concerns that a major player in the market could pull out and spark a crisis within the criminal justice system, the National Audit Office (NAO) report said.

“If suppliers did pull out of the market this could present a risk of service interruption, and lack of capacity could hold up criminal cases or cause them to collapse,” the report said. The study was carried out on behalf of the House of Commons Science and Technology Select Committee, which has criticised the Government for closing down the loss-making forensic service without properly analysing how the private sector would absorb the work.

The MPs warned that “the Government was focusing on the financial bottom line” rather than an effective forensic science service.

Three companies have cornered more than 90 per cent of the private forensics market that is worth between £60m and £81m annually, according to the industry and the NAO report.

Forensic pioneer Professor Peter Gill described a potential shift to in-house DNA testing as 'disastrous' (Science Photo Library) (Science Photo Library/Getty Creative)

While the size of the private sector forensics market has declined, the police’s own in-house laboratory work has increased from £113m in 2012-13 to £122m. Only one force has entirely outsourced its forensic science work, the report found.

In the face of budget cuts, the NAO found that police were tailoring their requests for forensic work rather than ordering a range of tests.

Professor Peter Gill, the pioneer of mass genetic profiling, said that the shift to in-house DNA testing would be “disastrous” with scientists under pressure to come up with results to secure convictions.

“Forensic science is now becoming police-controlled,” Professor Gill told The Independent. “It’s difficult enough when you’re not working for the police; you’re put under a lot of pressure to report what the police want you to report.

“If you’re not protected from that, then the more vulnerable forensic scientists are going to report cases wrongly. I’m absolutely convinced this is happening now. You can’t put forensic science solely in police hands. It would be disastrous.”

The privatised market is headed by LGC which provided the forensic breakthrough that led to the jailing of two of the killers of Stephen Lawrence after a re-examination of the clothes worn by the dead teenager and items found at the suspects’ homes.

But it was behind a mix-up at its main laboratory that led to an innocent man being wrongly accused of rape for months. It was also criticised after a typing error resulted in police chasing an unidentified suspect in the “spy-in-the-bag” death case of MI6 man Gareth Williams. It later emerged that the DNA came from a police scientist. The private sector told NAO researchers that declining profits could make it difficult to properly invest in research and development for future advances in DNA.

An error led to police chasing an unnamed suspect in the Gareth Williams ‘spy-in-the-bag’ case (PA)

“The private forensic science market has not taken up the slack and is struggling,” said Andrew Miller, chairman of the Science Select Committee. “And worryingly the NAO warn that this lack of capacity could put criminal cases at risk of collapsing.”

He said that the Home Office had failed to come up with a clear strategy for forensic work and failed to consider the wider implications for the criminal justice system.

“We warned back then that the Government was focusing on the financial bottom line without due consideration to the impact on forensic science research and development, the capacity of private providers to absorb the FSS’s dominant market share and the wider implications for the criminal justice system. This new paper seems to confirm the committee’s fears,” he said.

Police said that the shrinking market was driven by falling crime, with fewer tests needed for burglaries and killings. Reduced crime was the reason why the FSS lost £2m a month and led to its closure, said Chris Sims, the Chief Constable for the West Midlands and national police lead on forensic science.

He said that none of the “big three” – LGC, Cellmark and Key – had indicated they intended to withdraw from the market. “I know that they recognise that it’s a market that’s declining in overall size,” he said. “We obviously would not want any of those three providers to pull out.”

The report also highlighted that police labs could undercut the private sector by delaying meeting UK standards and that the regulator lacked powers to enforce the standards.

LGC, the biggest provider with 45 per cent of the private market, said it was continuing to invest despite the problems. “There is a degree of uncertainty because of insourcing and budget cuts but we wish to stress that the private sector delivers some of the best forensic delivery times in the world to police forces,” said Dr Mark Pearse, commercial director of its forensic services.

A Home Office spokesperson said: “In 2013-14 the National DNA Database produced 24,953 matches between crime scenes and known individuals, including matches in 183 homicides and 482 rapes.

“Police spending with private forensic suppliers has reduced for a number of reasons, such as falling crime, lower costs due to improved processes, and greater competition.

“It is for police and crime commissioners and chief constables to decide how to spend their budgets. However, we monitor the market closely to make sure it remains competitive and it continues to provide forces what they need.”

Inexact science: Innocent man jailed

The arrest of an innocent man for rape because of a mix-up over DNA samples has previously led to calls for an inquiry into the closure of the Forensic Science Service.

Adam Scott was arrested and held in custody for five months over an allegation of rape even though he was hundreds of miles away from the scene of the crime.

His DNA had been retrieved from a “spitting incident” in Exeter but became mixed up during the analysis of genetic material taken from a rape victim in Manchester.

The problems were attributed to “human error” at the headquarters of LGC forensics, when a plastic tray containing a sample of Mr Scott’s DNA was wrongly re-used for the analysis of a swab taken from the rape victim.