The High Court underlines the importance of local authorities’ duty of candour

In the recent case of R (Montaño) v London Borough of Lambeth, the High Court emphasised the importance of public authorities and their legal advisors having candour and cooperation at the forefront of their minds and actions from the outset and throughout judicial review proceedings.

19 April 2024

Woman holding documents

Judicial review is a distinctive type of litigation, which is grounded in the principles of fair and rational decision-making, the public interest, and upholding the rule of law. Therefore, parties to these proceedings in the UK are subject to high standards of conduct, including abiding by the duty of candour. 

In the recent case of R (Montaño) v London Borough of Lambeth, relating to a local authority’s administration of housing allocation policy, the High Court criticised the local authority’s failure to comply with the duty. The decision emphasises the importance of public authorities and their legal advisors having candour and cooperation at the forefront of their minds and actions from the outset and throughout judicial review proceedings. 

What is the duty of candour?

The duty of candour applies to all parties in judicial review proceedings, requiring them to frankly and proactively disclose all information relative to the questions before the court. This is a very high standard of disclosure, designed to ensure that the court has a true and complete understanding of the decision-making process at issue, in contrast with the rules of standard disclosure applicable to most civil claims. 

The duty kicks in at the earliest opportunity in a judicial review case. The Treasury Solicitor’s Department Guidance provides that it is to be exercised from the moment that a “department is aware that someone is likely to test a decision or action affecting them”. The same applies to the decisions made by public authorities in Scotland. This is a broad and all-encompassing responsibility, informing parties’ approach to internal information-gathering exercises, and communication with the court and other sides in relation to all information, documents, and submissions. 

Despite the duty applying to all parties, case law has demonstrated particular scrutiny when the defendant is a public authority. The rationale behind this was explained in R (Hoareau) v Secretary of State for Foreign and Commonwealth Affairs:public authorities are not engaged in ordinary litigation, trying to defend their own private interests. Rather, they are engaged in a common enterprise with the court to fulfil the public interest in upholding the rule of law”.

The High Court’s decision in R (Montaño) v London Borough of Lambeth

In this case, Ms Montaño sought judicial review of Lambeth’s refusal to exercise their discretion when she requested that they backdate her registration date on the housing register. The request was initially acknowledged, but no response was received until she initiated judicial review proceedings, with the local authority stating that the registration date was automatically set. 

Lambeth stated that it was a “hard fact” that they had no discretion to backdate the date of registration, to which Ms Montaño responded with detailed evidence of backdating occurring in other cases. 

In addition to the High Court’s ruling that the local authority’s decision not to consider exercising its discretion amounted to acting unlawfully, the court strongly criticised the local authority’s failure to discharge their duty of candour throughout the proceedings. The court said that: 

“[the local authority] should have filed evidence to assist the court with a “full and accurate explanation” in response. Instead, it responded simply by way of assertion in its Skeleton Argument. It did not answer any of the reasonable requests made by the Claimant for clarification… Equally unsatisfactorily, it failed to serve the Guidelines until prompted to do so by its eleventh-hour application to the court for permission to take part in [the substantive hearing in] these proceedings.”

Moreover, the court emphasised that pressure on time and resources is not an acceptable excuse for a public authority’s conduct to fall short of the standard expected by the duty of candour.


The decision is a reminder to all those involved in judicial review across the UK, particularly those acting on behalf of public authorities and to their legal advisors, to diligently and collaboratively comply with the duty of candour required of them from the earliest stages of proceedings. Failing to do so not only defeats the principles underlying judicial review and disclosure, but may result in opprobrium from the courts. 

The focus of judicial review is not on private interests, but to improve the standard of public decision-making by facilitating the court to reach the correct result. It is critical, therefore, that local authorities disclose important documents relating to their decisions and only make assertions that are supported by facts. 

If you would like to discuss any of the issues raised in this article or need assistance in such a matter, please contact our litigation and dispute resolution team.


This article was co-authored by Catherine Templeton