Joint circular no. 113 – Contamination Elimination Database (CED)

The provision of elimination samples is a requirement of UKAS Accreditation and the Forensic Science Regulator’s Codes and related guidance documentation

Employers’ Secretary, Sarah Ward
e-mail: [email protected]
Trade Union Side Secretary, Ben Priestley
e-mail: [email protected]

To:    Police and Crime Commissioner (copy Chief Exec &Treasurer)
Chief Constables (copy Force Personnel/HR Manager/Payroll Manager)

cc:    PSC Members
Scotland and MPS (for information only)

17 February 2021


The provision of elimination samples is a requirement of UKAS Accreditation and the Forensic Science Regulator’s Codes and related guidance documentation. This is in respect of anti-contamination measures and is necessary to demonstrate and provide evidence that police forces have in place, appropriate steps to reduce and remove contamination wherever possible, safeguarding the integrity of samples and offering a quality service to both suspects and the victims of crime.

During the last two years there has been a national drive to transfer samples from the PED (Police Elimination Database) to the CED (Contamination Elimination Database), given that the PED does not enable as robust anti-contamination searching as the CED and which is set to be decommissioned in the future.

It is acknowledged that there are concerns regarding the move of staff samples from the PED to the CED and subsequent police activity and the process that would be engaged, should a past contamination event be identified.

The PSC believes and seeks to reassure forces and staff that DNA profiles held on the CED are primarily for the identification of a contamination event and for elimination purposes. In the event that a crime stain from another force area matches a DNA profile held on the CED, information related to the personal data (collar ID and date of birth) held against the matching profile on the CED may not be used and forces will need to re-sample under PACE if they suspect criminal activity.

In order to evidence continuous improvement in the reduction of contamination, forces are required to undertake activity to determine the possible nature of any contamination event. The line manager of the police staff employee whose CED Elimination profile has matched a crime stain will be advised. The line manager will be asked to discuss the event with the individual to attempt to establish a likely or possible cause for the contamination event so that it can be understood and future occurrences may be avoided where possible and the crime scene sample profile deleted.

In the event that the employee is unable to offer any explanation for the contamination event, this will be recorded by the line manager as “source of contamination not known”.

Yours sincerely

Ben Priestley, Trade Union Side Secretary
David Algie, Employers’ Side Secretariat