What does the principle of “legality” mean in public law?
20 May 2026
Ismailov (No.2) v. Foreign Secretary, Saini J
The claim of a lack of “legality” as part of a public law challenge is often advanced in a rather free-floating way. The judge, Saini J, does some very useful clearing up of terminology in this case about a challenge to economic sanctions. The case also contains a crisp summary of other public law principles, with an application well beyond the sanctions context.
The case
Here’s a brief account of the facts and the Russian economic sanctions regime in dispute.
Sarvar Ismailov is the nephew of Alisher Usmanov. Usmanov is said to be closely associated with Vladimir Putin; in sanctions legal terminology, he is an “involved person” who may be subject to sanctions. But what about his nephew?
Ismailov had lived in the UK from the age of 13, but he and his family left the UK in March 2022 (shortly after the invasion of Ukraine) and now appears to live in Dubai. He is now 31.
Shortly after his departure, in July 2022, the UK sanctions regime (via the enabling Sanctions and Anti-Laundering Act 2018 – SAMLA – and underlying Russia Regulations) was modified so that you could be potentially designated as subject to sanctions if you were an “immediate family member” of an involved person– unsurprisingly defined as including nieces and nephews: [20] of the judgment for a summary of the modified regime.
This brought Ismailov into the frame, because of his uncle.
But despite being in the frame, a person is not designated yet. The Foreign Office (FO) then considers whether there are good reasons for the individual to be designated – and it found these in respect of Ismailov.
This designation was the overall target for this challenge.
One of the incidental interests of the case is seeing why the FO thought that Ismailov should be designated: [65] of the judgment, setting out his business ties, including Usmanov/Usmanov companies’ past common involvement with Everton Football Club. So they were not just nephew and uncle. It was thought by the FO that Usmanov might use Ismailov (wittingly or unwittingly) as a vehicle for sanctions-busting, if Ismailov was not sanctioned; and, in reverse, Ismailov, if sanctioned, might put pressure on his uncle to distance himself from investments of strategic significance to Russia.
In legal terms, Ismailov’s challenge was to
- the July 2022 change in the law about family members via the new regulations, and
- the maintenance of Ismailov’s designated status after an administrative review in 2023-2024.
There are statutory routes of review of a decision to designate, namely an administrative review by the Minister (s.23(1)(b) SAMLA) and the court review which came before Saini J (s.38(1) SAMLA). We are not in common-law judicial review territory, which difference, as we shall see, affects the standard of review.
For reasons which I will explain, all of Ismailov’s challenges failed.
The challenges to the legal regime
Ground 1: legality
Ismailov said that the change in the law in 2022 which introduced the “immediate family member” test, enlarging the number of potential designated people, was unlawful. The nub was that a liability to designation by “pure accident of birth” offended the legality principle, due to its arbitrariness and the connected lack of direction given to the FO when exercising its discretion as to who should or should not be designated.
The judge probed Ismailov’s counsel on how this converted into potentially valid public law complaints. The judge’s analysis at [84]-[101] is an extremely helpful pinning down of these various arguments.
- First, public law legality is a “narrow principle of construction and no more”: [86]. “So, the principle of legality in the public law sense is directed at seeking to ascertain the true intention of Parliament, as the basis for the interpretation of legislation. In short, it operates as a rule of construction under which general or ambiguous statutory language may be construed in a manner that preserves fundamental rights. The principle means not only that Parliament cannot itself override fundamental rights by general or ambiguous words, but also that it cannot confer on another body, by general or ambiguous words, the power to do so.”
This could not help Ismailov here. The statutory scheme was clear and unambiguous: [87].
- The second strand of potential unlawfulness, the judge headed ECHR legality: [88]. Did the legislation at issue have the “quality of law” for ECHR purposes? Were the laws unclear and unambiguous? They were not: [91], and this had been decided by the Court of Appeal in the previous sanctions case of Khan [2025] EWCA Civ 41, where the unsuccessful challenge had asserted that the phrase “associated with” was “not in accordance with law”.
- The third strand was proportionality. As the judge noted at [99], proportionality does not amount to a freestanding domestic basis for challenging subordinate legislation – here introducing the “immediate family” extension of scope: “…the only route by which the Claimant can succeed on this sub-ground is by demonstrating that the Russia Regulations fail the so-called ab ante test for proportionality: that is, they are likely to give rise to an unjustified interference with Article 8 ECHR in all, or almost all, cases.” This was not to be established in this claim.
Ground 2: ultra vires
This ground ([102]-[117]) was intricate. It was argued that the statutory instrument about immediate family was ultra vires because it went beyond the EU foundation which had led to SAMLA. The detail was complex, but the answer wasn’t; once the EU rules were transposed post-Brexit, there was a freestanding domestic scheme which could go its own way unconstrained by its EU origins as and when the UK wished it to do so.
Ground 3: Carltona
Ismailov said that designation decisions must be made by the Minister individually, rather than by the civil servants who reported to them. The judge rejected this. This argument is a perennial one, and in most cases is answered by the 1943 case of Carltona. The judge summed this rule elegantly at [126]:
“I would prefer to say that as a starting point, one should proceed on the basis that officials can perform ministerial functions, but that starting point must yield to a clearly expressed contrary will expressed in the language in a statute.”
The pragmatics of this rule date back to its 1940s origin, but are illustrated by this instance; there are now 3,252 designated persons under the Russian Regulations, and there are an additional 36 UK sanction regimes over and above those applicable to Russia. If an individual decision in each case under each regime were required from the Minister this would place a considerable burden upon them. But those who want to dive into this issue will find the case law and analysis summarised economically at [122]-[130].
Challenges to the individual decision to maintain the designation: Grounds 4 to 7
These are of less general interest, but essentially the law is derived from the Shvidler sanctions case in the Supreme Court – covered in the blog here.
This approach is summarised at [27]-[34] of Ismailov. In short, a review by a court of a sanctions decision involves the court making its own assessment of whether the decision is proportionate to a legitimate aim, unlike the conventional public law review approach; but that does not mean that the court is the primary decision-maker, because it has to respect the views of government on issues of national security and international affairs which feed into that decision.
Ground 4: proportionality
The judge found that the particular decision was proportionate, adopting the well-established Bank Mellat tests; it had a legitimate objective, it was rationally connected to the objective, there was no less intrusive measure, and it struck a fair balance between individual rights and the general community: [134]-[148]. All straightforward stuff.
Ground 5: irrationality
An unpromising argument once the claimant had failed to establish lack of proportionality, and so it proved: [153]-[158].
Ground 6: arbitrariness
The argument here was that there was a difference in treatment between Ismailov and other relatives of designated persons, with the example being given of Roman Abramovich’s children who were not designated: [159].
The judge [161] doubted whether there was a freestanding principle of public law requiring equality of treatment under SAMLA, but in any event Ismailov had not shown that the potential comparators (e.g. Abramovich’s children) were in a similar position even if there were such a principle. The argument also ran into difficulties with precedent, not only Shvidler but also a decision of this judge in Dana (involving a Belarus company), upheld on appeal: [163].
Ground 7: Public Sector Equality Duty (PSED)
This is a frequent claim in public law challenges. It can be a potent argument, but not here.
Various points were taken. The first was that the various iterations of the Russia Regulations were subject to PSED assessments, which did not look at the specific impact of the immediate family amendment. This was dismissed by the judge on his view of the paperwork.
The judge also ruled that, irrespective of this, PSED did not give rise to a freestanding protected characteristic of being a family member, and therefore there was no duty to have regard to the impact of a policy on familial status: [178]. This finding may have wider implications.
This element of the claim was also dismissed on the basis that the PSED had no territorial effect, given that the claimant lived abroad, and did so at the time of the challenged decisions; he was a citizen of Russia, Uzbekistan and Cyprus but not the UK: [181].
Finally, there did not have to be a PSED assessment in respect of every individual designation decision: [183].
Footnote
Those who have read the excellent 2026 documentary thriller by Patrick Radden Keefe, London Falling, will recognise a name which is the same as our unsuccessful claimant, in a potential Russian oligarch context. More than that I cannot say, for fear of spoilers, but it casts no conceivable slur on our nephew – for reasons which will become readily apparent if the book is read – which please do.
