Britain’s justice system will take a “backward step” if the Government closes its Forensic Science Service (FSS) – which has a laboratory in Wetherby with 200 employees – experts warned.

And the quality of British justice would suffer because the free market would not provide some more expensive forms of analysis crucial to police investigations, they wrote in a letter to a national newspaper.

Staff at the FSS laboratory in Sandbeck Way conduct highly specialised and time-consuming work extracting DNA from old or decomposed material or human remains.

Using low copy number techniques, they can gain a profile from samples that are invisible to the naked eye.

The work has helped snare killers such as Soham murderer Ian Huntley and Suffolk Strangler Steve Wright.

Winding up the service, one of the town’s biggest employers, would see the country lose its position as world leader in crime-scene investigation, they suggest.

Meanwhile, the Home Office’s decision to break-up the Forensic Science Service (FSS) has been met with “disbelief and dismay” around the world, they claim.

The letter, signed by 33 leading forensic scientists, follows a backlash earlier this month against the planned closure of the service, which employs 1,600 staff nationwide, but makes an operating loss of £2 million per month.

It was signed by 33 international forensic scientists, including Prof Sir Alec Jeffreys, who pioneered DNA fingerprinting, a technique credited with revolutionising criminal investigation in the 1980s.

Prof Niels Morling, president of the International Society for Forensic Genetics, who coordinated the letter, said the appeal to save the FSS had drawn support from scientists around the world.

“So many of us have benefited from the research, development and education offered by the FSS – a worldwide network of scientists is grateful to the FSS and to British society,” he told The Times.

“Our plea to the British Government is: ‘Please consider what you will do next – ask where (you) will be in five or ten years time if this goes ahead?’ “Where will the research be? Who will do the development work? Who will look after the quality of forensic science in a competitive market? Closing the FSS is a backward step.”

In their letter, the scientists claim the service ensured Sir Alec’s DNA discovery could be transformed into practical crime-scene analysis, now used across the globe.

“These advances paved the way for the introduction of national DNA databases to routinely match crime-scene material to suspects with previous convictions ... The FSS has truly been a leader in European forensic practice as well as research,” they said.

And they questioned the capacity of private-sector laboratories to provide a comparable alternative.

According to the Home Office, the FSS is likely to run out of money by January.

It is expected to be wound up by March 2012.