More than 1.7 million DNA profiles of innocent adults and children have been deleted from the national database, ministers have revealed.
As part of the Government’s commitment to slim down the amount of information held by the state, more than 1.6 million fingerprint records from innocent people have also been deleted.
Some 480,000 of the DNA profiles removed from the database were from children, Criminal Information Minister Lord Taylor of Holbeach told Parliament.
In a written statement he said the Government had ” delivered its commitment to reform the retention of DNA and fingerprint records by removing innocent people from the databases, and adding the guilty”.
Some 7,753,000 samples, containing “sensitive personal biological material”, have been destroyed because they are no longer needed as they have been used to create a profile.
Lord Taylor said 1,766,000 DNA profiles from innocent people had been deleted from the National DNA Database (NDNAD) and 1,672,000 fingerprint records had been removed from the national fingerprint database.
He added: ” At the same time, 6,800 convicted murderers and sex offenders, not on the database under the previous Government, have had their DNA taken and added to the database.
“These records will be kept permanently, as will those of every convicted adult on the database, to ensure our databases remain a powerful tool for fighting crime.”
A Home Office spokesman said: “Through the Protection of Freedoms Act we are restoring common sense to the system by ensuring that only those convicted of a criminal offence will have their DNA retained indefinitely.
“We are adding the DNA of criminals who were not on the database under the last government, and getting rid of it where people have done nothing wrong.
“Forces will be able to retain DNA from someone arrested and not charged for up to three years, but only with permission from the Biometrics Commissioner. And all DNA samples taken by the police are checked against the national database before deletion.”
As of March 31 the NDNAD held 6,737,973 DNA profiles from individuals – although the Home Office said that figure will now be “considerably smaller” as a result of deletions – and 428,634 DNA profiles from crime scenes.
The NDNAD holds profiles from all UK police forces including England, Wales, Scotland and Northern Ireland, but only the profiles belonging to England and Wales forces are subject to the restrictions in the Protection of Freedoms Act.
Scotland and Northern Ireland have their own laws on DNA retention and separate databases but profiles loaded to these databases are also loaded to the NDNAD due to the likelihood of offenders moving between UK countries.
According to the NDNAD strategy board’s annual report, data from p olice forces in England and Wales shows that in 2012/13, 19,147 crimes were solved following a match with a database profile.
But the report highlighted a blunder by Cellmark, one of the private laboratories carrying out DNA work, which resulted in one suspect’s DNA being matched to two crime scenes instead of one.
“Following an investigation into the issue, it appears that the root cause of the problem was a handling error by the laboratory scientist during the dilution process that forms part of the DNA analysis process within the laboratory,” the report said.
“The error led to two samples being processed from the one case, rather than two samples from two unconnected cases being processed; this led to one person’s DNA profile being matched to two crime scenes rather than just the one. Retesting confirmed that there were two offenders.
” The laboratory reviewed 550,000 previous samples and identified 268 for detailed review. No further errors were found, and measures were put in place to prevent it happening again.”