Prospect, the union that represents more than 1,000 forensic scientists and other professionals within FSS, said the decision will make a mockery of the criminal justice system by denuding it of impartial, independent advice.

“Cost will now determine justice in the UK,” said Mike Clancy, Deputy General Secretary of Prospect.

“The government is putting its faith in an untested market to deliver forensic science at a time when it has never been more important to the detection of crime. Its actions will destroy a world-class body that is the envy of every police force in the world, in the name of saving a few million pounds.

“It is nothing short of astounding that this decision has been taken without any consultation with staff or stakeholders. This is typical of the coalition’s approach to decision making, as shown by its arbitrary closure of the Audit Commission this summer. It is exactly the kind of arrogant behaviour by this government that the House of Lords Constitution Committee warned of only a few weeks ago.

“What is even stranger is that the decision is directly at odds with the government’s stated aim of encouraging public bodies to share services.

"Instead, it will create a complex market where police forces will have to develop their own capacity for analysis and support in forensics, multiplying duplication across the board.”

Clancy added that the break-up of FSS would lead to an over-emphasis on profits and commercial relationships to the detriment of the quality of the science.

Far from taking on FSS work, police forces are already cutting back on their own in-house forensic facilities in the face of budget cuts next year.

FSS has enjoyed an enviable reputation as being at the forefront of forensic research and development, typified by its pioneering work on the DNA and national firearms databases.

The union warned that national security is also threatened by today’s decision as the transfer of intelligence information, currently shared with agencies such as the anti-terrorist branch of the police and security services, will be impeded by the bodies that will take over FSS work.