Guidance

Forensic information databases strategy board policy: DNA familial searching policy for the National DNA database (accessible)

Published 16 September 2026

Authorised by: Z. Ledger

Date: 7th May 2026

Job Title: Head of Unit

Please note that the content and the layout of this document are controlled by the NDNAD Delivery Unit Quality Team and are not to be altered in any way.

We are constantly looking for ways to improve our policies and procedures. Constructive feedback both positive and negative is always welcome. Please submit your feedback or proposals for change to: FINDS_Quality_Management@homeoffice.pnn.police.uk.

Identification

Policy Reference Number and Policy Title: FINDS-P-021 – The Forensic Information Databases Strategy Board Policy: DNA Familial Searching Policy for the National DNA Database.

Ownership

Organisation and Department Responsible: FINDS - Head of Unit/Scientific Services.

Distribution

Forensic Service Providers, Police Forces, NCA MICS and the FIND Strategy Board.

Recent Revision History

Issue Number	Issue Date	Summary of changes
11	07/05/2026	DCR1920 – Rewrite to reflect the centralised familial service undertaken by FINDS.

The full revision history, references and definitions sections can be viewed at the end of this document.

Objective and Scope

This document sets out the policy governing the use of the National DNA Database for the purposes of familial DNA searching.

Familial DNA searching helps police investigate serious crimes and identify unidentified human remains. It supports investigations by narrowing lines of enquiry and reassures the public that offenders can be identified and brought to justice.

The policy also protects the civil liberties of people whose DNA has been taken in the UK.

NCA Major Crime Investigative Support (MCIS) teams play an important role in supporting investigations where familial DNA searches are being considered. Trained MCIS staff advise investigative teams on the available approaches and the suitability of a familial search. Following approval, MCIS support investigations by assisting with the interpretation and understanding of search outcomes. Although this activity is outside the scope of this policy, MCIS works closely with FINDS on behalf of the FIND Strategy Board to ensure the appropriateness of familial searches.

Forensic Service Providers (FSPs) play an important role in supporting investigations through scientific activities; however, these activities are outside the scope of this policy.

In Scope

This policy covers:

1. The searching of DNA profiles generated from crimes and unidentified human remains where the identification of the individual whose DNA was collected remains unknown following a search of the National DNA Database (and in the case of unidentified human remains includes the Missing Persons DNA Database).

2. The use of familial DNA searching on the NDNAD where the crime was not committed in the UK or the DNA profile was not generated in the UK.

Out of Scope

This policy does not cover:

1. Familial searching on the Scottish DNA Database, albeit Scottish data stored on the NDNAD will be included in the search.

2. Familial searching on the Northern Ireland DNA Database, albeit Northern Irish data stored on the NDNAD will be included in the search.

3. Familial searching of UK DNA profiles outside of the UK (please refer to FINDS-P-040 International DNA and Fingerprint Exchange Policy for the United Kingdom).

4. The collection and DNA profiling (including DNA profile test methods) from any person because of a familial Search and subsequent investigations.  Investigators must ensure compliance with appropriate policy and legislation.

Responsibilities

Organisation	Responsibility
FINDS	The Forensic Information Databases Service (FINDS) (part of the Home Office) is defined as processor on behalf of the National Police Chiefs’ Council (NPCC) Lead (Chair of the FIND Strategy Board).  As defined within the Strategy Board governance rules, FINDS are responsible for the integrity and protection of the data held on the NDNAD and any associated database relating to missing persons.
FSPs	FSPs are responsible for assuring that they comply to legislative, regulatory and FIND Strategy Board/ FINDS policy requirements, to ensure the integrity of the records held on the NDNAD. FSPs are processors on behalf of the police force where the DNA sample was taken, and in relation to this policy, responsible for generating a DNA profile that forms the input for familial searching.
Police Forces	Forces, have the responsibility: 1. To ensure all data in relation to a familial search are used only for the purpose of the investigation or the identification of a victim in the case of familial searches being used to identify body parts for which they are made available. 2. To ensure that applications for familial searching adhere to this policy.

Background

The familial searching is based on the following principles:

• DNA is inherited, and all members of a biologically related family will share a proportion of their DNA. A child inherits approximately half of their DNA from their biological father and half from their biological mother. The extent to which biological siblings share DNA is variable; however, they will generally share a greater proportion of DNA with each other than with unrelated individuals.

• It is possible that one or more biologically related members of a family may have their DNA profile held on the NDNAD. However, in some cases, an individual may have no known biologically related family members represented on the database, which may limit the potential effectiveness of a familial DNA search.

• Where a familial DNA search is used to support a criminal investigation, it is relevant that many families reside within relatively small geographic areas. Research also indicates that offenders are more likely to commit offences close to where they live, which may assist in focusing investigative enquiries.

• There will be occasions where familial DNA searches represent the only viable means of achieving identification and providing closure in cases involving unidentified human remains.

Familial DNA searching is used to identify potential suspects or to assist in the identification of unidentified human remains through two recognised types of biological relationship:

1. Parent/Child Search

This type of search identifies DNA profiles held on the NDNAD that may represent individuals who are biologically related as a parent or child of the person of interest (for example, an offender or an unidentified individual).

2. Sibling Search

This type of search identifies DNA profiles on the NDNAD that may represent individuals who are biologically related as siblings (brothers or sisters) of the person of interest, such as a potential suspect or unidentified human remains.

Please note that although the searches are referred to as “parent-child” and “sibling” it is possible that individuals could be returned who are another relation to the unknown individual – uncle/aunt, nephew, niece, grandparent etc.

Policy

This policy of the FIND Strategy Board considers legal requirements relating to the creation, operation and maintenance of the National DNA Database, as well as legal, ethical and moral obligations with respect to use of the DNA data and samples taken under PACE, in particular the Human Rights Act 1998 and the Data Protection Act 2018.

FINDS will manage the requests on behalf of the FIND Strategy Board.  Where the request complies with the rules stated in the case requirements section within the policy (below), then FINDS will approve the search.  If the rules are not met, then they will refer it to the Chair of the FIND Strategy Board, consulting with the appropriate groups (including: NCA specialist advisors, Science and Technology Ethics Advisory Committee (STEAC), Biometrics Commissioner (BC) and the Information Commissioner’s Office (ICO)) to ensure the request has been considered from a moral, legal and ethical perspective.

Where the familial searching relates to a Scottish DNA profile within the NDNAD, then the lead for FINDS may wish to consult with the Scottish Biometrics Commissioner to ensure that there is no conflict with the statutory Code of Practice in Scotland as approved by the Scottish Parliament.

Case Requirements

Familial DNA searching will normally be used only in relation to the most serious offences, namely murder, manslaughter, and sexual offences, or to assist in the identification of unidentified human remains.

In all other circumstances, familial DNA searching will be undertaken only where the Chair of the FIND Strategy Board (or their nominee) agrees that its use is justified in the specific circumstances of the case, and where it is reasonable to expect that the search may contribute substantially either to the detection of the offence or to establishing the identity of unidentified human remains.

Centralised Familial Searching within FINDS

Prior to 1st June 2026, familial searches using nominal information from the NDNAD had been undertaken by two different FSPs within the UK. From 1st June 2026, all familial searching against nominals on the NDNAD will be centralised and undertaken by FINDS.

Familial searching against nominals on the NDNAD will only be permitted through FINDS using DBLR™ software.

A DNA profile derived from a crime stain or from unidentified human remains and submitted for familial DNA searching must meet the following criteria:

1. Shall contain, as a minimum, numeric allele data for 18 alleles within the SGMPlus markers.

2. Should be loaded to and retained on the NDNAD and/or the MPDD (if the DNA profile relates to unidentified human remains).

3. Shall have no viable exact matches reported from the NDNAD to a person profile.  Where matches have been identified, case investigations must evidence that those matches have been eliminated.

4. Shall have no viable matches reported from the MPDD (in reference to unidentified human remains) to a person profile. Where matches have been identified, case investigations must evidence that those matches have been eliminated.

5. Shall have an acceptable level of certainty that the DNA profile relates to the person of interest (e.g. potential suspect or unidentified human remains) and that the result is not due to contamination of the sample along the chain of custody or during examination/analysis or that it is ambiguous as to if the sample is related to the crime.

6. The investigation should have considered the taking of reference elimination samples (if required) before a familial search is undertaken.

7. It is desirable that there should be additional information surrounding the DNA profile subject to a familial search, such as age range or an identifiable link to a geographical area. This additional information will assist in the prioritisation of any potential relatives revealed by the familial search.^{[footnote 1]} However, this is not essential and searching purely on genetic likelihood remains a valid option.

Search Authorisation

Each familial searching of the NDNAD needs to be documented and requested on FINDS-F-081 Authorisation Form For Routine Familial Searching.

Search Support

Each familial search must be assessed and supported by the NCA MCIS.

Force may also want to liaise with their Forensic Service Provider to obtain any scientific guidance in relation to the familial search.

Searching and Results Handling

Familial searches will be conducted using extracts of legally retained SGMPlus and DNA‑17 arrestee DNA profiles held on the NDNAD, with searches strictly limited to these records. SGM profiles will only be searched with additional authorisation where no result is obtained, and the case timeframe makes this appropriate.

Prior to the search, barcodes will be checked to ensure no intervening database match has occurred. Likelihood‑ratio‑ranked results will be retained securely by FINDS, with only non‑DNA demographic data shared with the authorised requesting force and decrypted via NCA MCIS. Access to results will be tightly restricted to the investigation team, and all information obtained may only be used for the specific investigation and must be destroyed in line with policy if no longer relevant.

For further information please refer to Appendix A.

Exceptional Cases

Where a request to carry out a familial search of the NDNAD does not meet the requirements of this policy, full details of the request must be submitted in writing to the Chair of the FIND Strategy Board (or their nominee).

The submission must include sufficient case information to enable the Chair to assess the request on legal, ethical, and moral grounds. It must clearly explain:

• the public interest justification for conducting the familial search; and
• how the search forms an integral part of the forensic strategy for:
  • the investigation of the offence, or
  • the identification of unidentified human remains.

Where the DNA profile is partial and contains fewer than 18 alleles, the submission must also include:

• a clear explanation of why a partial profile should be searched; and
• supporting evidence demonstrating that any potential outcomes are likely to provide a meaningful and viable likelihood of identifying a familial relationship.

The Chair of the FIND Strategy Board (or their nominee) may, where appropriate, seek the views of the Biometrics Commissioner, the Information Commissioner’s Office, the Science, Technology, Ethics and Assurance Committee (STEAC), or any other relevant body, to obtain a balanced and independent assessment of the appropriateness of authorising a search.

Notwithstanding any external advice sought, the final decision on whether to authorise the search rests solely with the Chair (or their nominee) of the FIND Strategy Board.

Details of exceptional cases must be submitted in writing to FINDS, who will coordinate and submit the request for consideration by the Chair (or their nominee) of the FIND Strategy Board.

Destruction of Data

1. Arrestee DNA profile data will be destroyed from the NDNAD (and associated systems) in accordance with the requirements of legislation.

2. The direct outputs of a familial search (the FSP generated ‘Top 100 and Full output lists) that are kept within FINDS shall be retained in accordance with the FINDS Archive and Retention Policy.

3. The force and NCA will retain the generated Top 100 and Full output lists provided by FINDS under the provisions of CPIA and stored in line with force Policy.

4. If this information relates to profiles/samples from individuals, there is a legal requirement to destroy the information as soon as CPIA no longer applies.

5. There must be compliance to ensure matches are lawful and aligned to the Protection of Freedoms Act.

Non-UK Familial Searching

The use of the NDNAD for familial searching of non-UK related crimes shall not be permitted.^{[footnote 2]}

References

The following references should be used for additional information to this Policy

Title	Link
The Forensic Information Databases Strategy Board Policy for Access and Use of DNA Samples, DNA Profiles, Fingerprint Images, Custody Images, and Associated Data	FINDS-SB-P-002
Authorisation Form For Routine Familial Searching	FINDS-F-081

Definitions

Term	Definition
Crime Stain sample	A biological sample collected from material left at a crime scene
DBLR™ (Database Likelihood Ratios)	Is a software application for the calculation of likelihood ratios
Demographic Data	The information that identifies an individual or case investigation – not the DNA profile
DNA	Deoxyribonucleic Acid
DNA Profile	The outcome of an STR DNA test which may be represented as a series of numbers relating to the areas of DNA targeted by the test.
DNA Sample	A sample of biological material that contains purified DNA.
DNA-17	A DNA Test that targets 16 areas of DNA plus a sex marker.  All DNA areas in SGMPlus are contained within DNA-17.
Familial	Of or relating to a biologically related family
FINDS	Forensic Information Databases Service
FSP	Forensic Service Provider (for the purpose of this document, FSP only refers to a Forensic Service Provider approved by the FIND Strategy Board for interaction with the NDNAD)
MCIS	Major Crime Investigative Support
Missing Person	Anyone whose whereabouts cannot be established and where the circumstances are out of character or the context suggests the person may be subject of crime or at risk of harm to themselves or others (NB: a ‘wanted missing’ person is a person who cannot be located but is wanted in connection with a criminal investigation)
MPDD	The UK Missing Persons DNA Database
NCA	The National Crime Agency
NDNAD	The UK National DNA Database is a database containing DNA profile records of persons and crime stains that are compared against each other to identify matches to support criminal investigations. Matches are reported for persons to crime stains and crime stains to crime stains. The NDNAD can: 1. retain DNA profile records (the record is permanently loaded to the NDNAD) for continuous speculative searching against current, new or amended DNA profile records; or 2. have a DNA profile searched through a Non-Routine Speculative Search – where the searched record is not retained on the NDNAD. All DNA profiles retained on the NDNAD were generated from DNA samples taken in the UK by FSPs approved by the FIND Strategy Board.
PACE	Police and Criminal Evidence Act 1984 (as amended)
SGM	A DNA Test that targets 6 areas of DNA plus a sex marker
SGMPlus	A DNA Test that targets 10 areas of DNA plus a sex marker.  All DNA areas in SGM are contained within SGMPlus
Unidentified Human Remains	A body (or parts of a body) that have been located where no identification of the individual can be made. (NB: depending on the body part, it may be that the individual is not deceased).

Full Revision History

Issue Number	Issue Date	Summary of changes
1	03/07/2017	New document
2	08/09/2017	Update of references to FINDS
3	07/07/2018	DCR085 - Update in relation to Data Protection Act
4	06/08/2019	DCR318 - change from NCA being the authoriser to being supportive
5	23/11/2020	DCR360 - Updated NDNAD email address
6	06/01/2021	DCR533 - Updated NDNAD email address updated section ‘NDNAD profile release – to confirm/eliminate SGMPlus matches.
7	28/03/2023	DCR932 – Updates made to section: Validation, Proficiency and Acceptance Testing of Familial Searching.
8	24/10/2023	DCR1049 – Full review
9	18/08/2025	DCR1379 – Full document review - minor updates to reflect a Scottish DNA profile and rephrasing for unidentified human remains searching.
10	06/11/2025	DCR1838 – email address update Ethics group name change

Appendix A – Searching and Results Handling

1. An extract of SGMPlus and DNA-17 records will be generated containing legally retained (at the point of the generation) person records on the NDNAD.

2. The search must be limited solely to ‘arrestee’^{[footnote 3]} DNA profile records on the NDNAD.

3. Only SGMPlus and DNA-17 DNA profile data and barcode identifier information for arrestee DNA profiles retained on the NDNAD will be made available for a familial search.

4. SGM arrestee profiles will not be made available on a routine basis.  If no result has been found with the SGMPlus and DNA-17 subset, additional authorisation will be required to facilitate an SGM subset search.  An assessment of the appropriateness to use this subset will be untaken by FINDS, such as considering the age of the offence and the potential age of the relative(s) in the case.  SGM was the profiling system used between 1995 and 2001.  Cases from this time will be considered for the SGM subset search. Advanced notice is needed if a search is required against the SGM subset.

5. On the morning on which the search is to be conducted, the barcode will be checked either upon the NDNAD and/or the MPDD (case type dependent) to ensure that a match has not occurred on the database in the intervening period between request and search.

6. Likelihood Ratio ranked results output of a familial search shall be retained within FINDS (in line with the ‘Destruction of Data’ section above) who will generate the associated demographic data for the records from the NDNAD. These records shall not contain DNA profile data and shall only be transmitted to the nominated authority within force and the password sent to NCA MCIS to enable them to unencrypt the data format.

7. On occasion, the demographic data for an arrestee’s DNA record may not be available at the point the demographic data is compiled.  This is likely to be due to the deletion of the record in accordance with the requirements of the Protection of Freedoms Act 2012 after the NDNAD extract is produced.

8. The familial match details should not be made available to ANY unauthorised person including for intelligence purposes. For the purposes of this policy the requesting force will be the controller of the data from the familial search and will authorise the access of the lists.  Access should be limited to the investigation team.

9. Any information provided to the police when interviewing potential relatives of potential offenders or identifying human remains shall only be used in relation to the specific case under investigation and not for any other purpose. The information shall be destroyed in line with force policy if it turns out not to be relevant to the enquiry.

1. Major Crime Investigative Support (MCIS) utilise a methodology for prioritisation which relies upon national statistics for age and geography. They can also access the Police National Computer (PNC)/ Law Enforcement Data Service (LEDS) and Queries using extended search techniques to assist this process, but both rely on additional non-DNA information within the case. ↩

2. This excludes crown dependencies the Channel Islands and the Isle of Man. ↩

3. People who have been arrested for a recordable offence or under an extradition arrest power. ↩