KPSS replied to Conservatives for Women. Their report is long but this must be the important part:
twitter.com/noxyinxxprisons/status/1598252686847401984?s=46&t=zFhPl8gZ83mYkkyo1N8cWw
kpssinfo.org/wp-content/uploads/2022/09/DBS-Checks-and-Identity-Verification.pdf
"The utility of a DBS certificate is predicated on the assumption that the information it displays is both accurate and complete. That is, that the information relates to the individual in respect of whom the certificate has been issued and that no relevant information about that individual has been omitted. The value of its contribution to safeguarding is dependent upon the accuracy and completeness
of the information supplied by the applicant. That information consists of identity documents and disclosure of any previously used names. Unlike other European states, the UK does not issue citizens with national identity cards. Instead other documents are used to establish identity, for example passport and driving licence.
The information displayed on a DBS certificate will only be that that linked to the identity(ies) disclosed in the application: these are the identities that
will be displayed on the certificate and used to search the Police National Computer, local police force systems and Barred Lists. The information shown on a certificate will not, therefore, include all relevant information relating to that individual where the applicant has not disclosed other identities they have used. The current DBS system relies on the assumption that these disclosures will be made accurately and fully, when there are reasons why they might not be. Omission could be deliberate, including for nefarious reasons. However, it could also be wholly innocent, for example where an applicant is absent-minded.
The DBS application process can be completed for all levels of checking, up to and including Enhanced with Adults’ and/or Children’s Barred Lists, using documentation that the individual can change to reflect a new identity. This includes passport and driving licence, which can be changed in respect of both name and gender, including on the basis of self-declaration. In some circumstances, the birth certificate can also be changed. By presenting documentation in a new identity and
by failing to disclose previously used names, an individual is able to hide their existing identity for the purposes of a DBS check. This means that the information displayed on the DBS certificate may be incomplete: where information on offending has been recorded on the Police National Computer or local police force systems against an identity that the individual is no longer using and has not declared, that information will not be retrieved during the check and neither that name nor any relevant data on offending linked to that name will be displayed on the certificate. Hence, the DBS check process contains safeguarding loopholes, which may be exploited by those wishing to cause harm to children or vulnerable adults."