HM Treasury v Ahmed [2010] UKSC 2 is a UK constitutional law and human rights case concerning the United Nations Act 1946 and the powers it grants to the executive to issue terrorism control orders.

The Supreme Court held that fundamental rights could only be overridden by express language or with necessary implication, and so the general wording of section 1 of the United Nations Act 1946 did not empower the government to pass the Order.

I would hold that, by introducing the reasonable suspicion test as a means of giving effect to SCR 1373(2001), the Treasury exceeded their powers under section 1(1) of the 1946 Act.

As Lord Hoffmann said in R v Secretary of State for the Home Department, Ex p Simms [2000] 2 AC 115, 131, fundamental rights cannot be overridden by general or ambiguous words.

The absence of any indication that Parliament had the imposition of restrictions on the freedom of individuals in mind when the provisions of the 1946 Act were being debated makes it impossible to say that it squarely confronted those effects and was willing to accept the political cost when that measure was enacted.

In my opinion the TO is ultra vires section 1(1) of the 1946 Act and, subject to what I say about the date when these orders should take effect, it together with the directions that have been made under it in the cases of A, K, M and G must be quashed.

As Lord Bingham memorably pointed out in R (Ullah) v Special Adjudicator [2004] 2 AC 323, para 20, the Convention is an international instrument, the correct interpretation of which can be authoritatively expounded only by the Strasbourg court.

It must be for the Strasbourg court to provide the authoritative guidance that is needed so that all the contracting states can adopt a uniform position about the extent to which, if at all, the Convention rights or any of them can be held to prevail over their obligations under the UN Charter.

Mr Singh submitted that the obligation under article 25 of the Charter to give effect to the SCRs directing the measures to be taken against Usama bin Laden, Al-Qaida and the Taliban had to respect the basic premises of our own legal order.

One was the right to peaceful enjoyment of his property, which could only be interfered with by clear legislative words: Entick v Carrington (1765) 19 Howell's State Trials 1029, 1066, per Lord Camden CJ.

The other was his right of unimpeded access to a court: R (Anufrijeva) v Secretary of State for the Home Department [2004] 1 AC 604, para 26, per Lord Steyn.

Some interference with the right to peaceful enjoyment of one's property may have been foreseen by the framers of section 1, as it authorises the making of provision for the apprehension, trial and punishment of persons offending against the Order.