Public Law Project v The Information Commissioner

Factual and Procedural Background

This decision concerns an appeal under section 57 of the Freedom of Information Act 2000 ("FOIA") against a Decision Notice ("DN") issued by the Information Commissioner on 26 July 2022. The appellant requested information from a public authority, referred to as the Home Office ("HO"), regarding the criteria used to assess which marriage referrals should be investigated as potential sham marriages. The HO disclosed two annexes but withheld some information under sections 31(1)(a) (prejudice to prevention or detection of crime) and 40(2) (third party personal information) of FOIA.

The appellant challenged the withholding of information, arguing for greater transparency, particularly concerning the criteria used by the triage model and the equality impacts on different nationalities. The Information Commissioner maintained that the exemptions were properly applied and opposed the appeal. The case was heard by a tribunal panel, which considered witness statements and legal arguments from both parties.

Legal Issues Presented

1. Whether the exemptions under sections 31(1)(a) and (e) of FOIA were properly engaged in relation to the withheld information concerning the triage model criteria.
2. Whether the public interest in maintaining the exemptions outweighed the public interest in disclosure.
3. Whether the Home Office held further information about the equality impacts of the triage model on different nationalities beyond what was disclosed.

Arguments of the Parties

Appellant's Arguments

• The appellant contended that disclosure of the withheld criteria would not prejudice the prevention or detection of crime, as some criteria have already been disclosed without detriment.
• Transparency and accountability require disclosure of the criteria used by the triage model, particularly to assess whether the model is discriminatory.
• There is a prima facie indication of indirect discrimination against certain nationalities, as evidenced by the equality impact assessment ("EIA") and related data.
• The appellant argued that it is implausible no further preparatory or analytical information exists beyond the disclosed EIA, and such information should be disclosed.
• The risk of "gaming" the system by disclosing criteria is overstated; many criteria are immutable traits not susceptible to manipulation.
• Disclosure would enhance public understanding of an important and controversial automated decision-making system affecting individuals’ rights to marry.

Respondent's (Information Commissioner) Arguments

• The Commissioner maintained that the HO was entitled to rely on sections 31(1)(a) and (e) to withhold the information because disclosure would likely prejudice the prevention or detection of crime and the operation of immigration controls.
• Disclosure could assist sham marriage organisers or organised crime groups in circumventing the system.
• Although two criteria were disclosed, disclosure of the remaining criteria would likely cause prejudice, justifying continued withholding.
• The public interest in protecting law enforcement capabilities and preventing crime is very strong and outweighs the public interest in disclosure.
• The Commissioner was satisfied, on the balance of probabilities, that no further information about the equality impacts of the triage model beyond the disclosed EIA is held by the HO.
• The Commissioner noted alternative legal mechanisms exist to address concerns about discrimination and automated decision-making, reducing the weight of the public interest in disclosure under FOIA.

Table of Precedents Cited

Court's Reasoning and Analysis

The tribunal found that the exemptions under section 31(1)(a) and (e) of FOIA were properly engaged. It accepted that disclosure of the withheld criteria would likely prejudice the prevention or detection of crime and the operation of immigration controls by enabling individuals or groups to adapt their behavior to evade detection, thereby undermining the immigration system. The tribunal emphasized that the Home Office is best placed to assess the nature and extent of such prejudice, consistent with parliamentary intent.

While acknowledging the appellant's concerns about indirect discrimination and transparency, the tribunal concluded that disclosure of the triage criteria would not effectively address these concerns and that alternative legal mechanisms exist to challenge discrimination. The tribunal noted that some criteria have already been disclosed, and that piecemeal disclosure risks a "mosaic effect" that could facilitate gaming the system.

Regarding the appellant's claim that further information beyond the disclosed EIA exists, the tribunal held that such information, if it exists, falls outside the scope of the original FOIA request and therefore is not part of the appeal. The tribunal relied on established case law that subsequent clarifications or expanded requests should be treated as new requests.

The tribunal gave weight to expert witness evidence on algorithmic transparency and discrimination but ultimately found that the public interest in protecting law enforcement and immigration controls outweighed the public interest in disclosure under FOIA. It also recognized that the automated triage system is part of a broader investigatory process, and that the final decisions impacting individuals are not made solely by the algorithm.

Holding and Implications

The tribunal DISMISSED the appeal.

The effect of this decision is that the Home Office is entitled to withhold the requested criteria under sections 31(1)(a) and (e) and section 40(2) of FOIA. The appellant's request for further information beyond the original scope was not upheld. No new precedent was established; the decision reinforces existing principles regarding the application of prejudice-based exemptions and the interpretation of FOIA requests. The tribunal encouraged the parties to seek resolution of any further information disputes through new requests or alternative legal mechanisms to conserve tribunal resources.