Chandler v DPP [1964] AC 763

Members of the Committee of 100 planned to occupy and immobilise RAF Wethersfield, a prohibited place, to protest nuclear weapons. Convicted under the Official Secrets Act 1911, they argued their aim benefited the State. The House of Lords held that obstructing defence facilities was a prejudicial purpose and upheld the convictions.

Facts

The appellants were members or supporters of the Committee of 100, a non‑violent civil disobedience organisation founded by Earl Russell. Their ultimate aim was to prevent nuclear war and to publicise facts about nuclear warfare, particularly through civil disobedience.

They planned a demonstration at the Royal Air Force station at Wethersfield, Essex, on 9 December 1961. Wethersfield was a prohibited place within the meaning of the Official Secrets Act 1911 and housed combat‑ready United States Air Force squadrons assigned to NATO and on constant alert.

As Lord Reid recorded, the plan, set out in a letter of 7 November, was to:

The working group at this end has finally decided in favour of a demonstration that will involve an attempt to occupy the base at Wethersfield. However the plan is for only a number of trained people to do this. The bulk of the demonstrators will squat by the entrances on the roadway. Our leaflet about the demonstration will simply state that we intend to immobilise the base and this is the information that will be released to the Press.

The appellants intended and desired that demonstrators should enter the base and, by obstruction, prevent aircraft from taking off for about six hours. They knew this was unlawful and that the Official Secrets Act might be invoked. In the event, demonstrators were prevented from entering, but that was immaterial to the conspiracy charge.

They were charged with conspiracy to commit and to incite others to commit a breach of section 1 of the Official Secrets Act 1911, namely:

for a purpose prejudicial to the safety or interests of the State to enter a Royal Air Force station belonging to Her Majesty at Wethersfield in the County of Essex

At trial before Havers J, the defence sought to adduce evidence that the base housed nuclear‑armed aircraft and that it was not in the interests of the State to have such weapons; hence immobilising the aircraft would, they said, be beneficial to the State. They also wished to show that they honestly and reasonably believed this to be so, supported by expert evidence on the effects and risks of nuclear weapons.

Havers J ruled that evidence designed to show that it would be beneficial to give up nuclear armament, or that the appellants honestly believed this, was inadmissible. He directed the jury that it was for them to say whether what the appellants conspired to do was prejudicial to the safety or interests of the State, but in substance indicated that, if they accepted the prosecution evidence about the airfield’s role in defence, they should find prejudice proved.

The appellants were convicted on 20 February 1962 and sentenced to terms of imprisonment. The Court of Criminal Appeal dismissed their appeals but certified that a point of law of general public importance arose and granted leave to appeal to the House of Lords.

Issues

1. Meaning of “purpose” in section 1 of the Official Secrets Act 1911

The central statutory question concerned the construction of the phrase:

for any purpose prejudicial to the safety or interests of the State

The issues included:

• Whether “purpose” referred only to the appellants’ ultimate political aim (nuclear disarmament) or also to their immediate aim (immobilising the base).
• Whether benevolent or ideological motives could negate a purpose otherwise prejudicial to the State.

2. Meaning of “safety or interests of the State” and who determines prejudice

The House had to consider:

• What “the State” means in this context.
• Whether it refers to the Government, the Crown, or the organised community.
• Whether it is for a jury to decide, on broad evidence including political and strategic material, whether a given purpose is prejudicial to the safety or interests of the State.
• Whether courts can entertain arguments that Government defence policy (e.g. maintaining nuclear weapons and bases) is contrary to the true interests of the State.

3. Admissibility of evidence challenging defence policy

The appellants argued that the trial judge wrongly excluded evidence:

• On the devastating effects of nuclear explosions, risks of accident or radar mistakes, and dangers of nuclear retaliation.
• On expert and factual matters said to show that nuclear armament was not in the interests of the State, and that immobilising nuclear‑armed aircraft would therefore be beneficial.

The question was whether such evidence was relevant to the statutory issue of “purpose prejudicial to the safety or interests of the State”.

4. Constitutional dimensions

The appeal raised broader constitutional questions about:

• The limits of the Royal Prerogative in relation to the disposition and armament of the armed forces.
• The extent to which courts may review or question defence and security policy in criminal proceedings.
• The role of the jury in deciding questions that have strong political content, such as the wisdom of nuclear deterrence.

Judgment

Construction of section 1: “purpose”

Lord Reid held that there was no difficulty about the appellants’ “purpose”:

The accused both intended and desired that the base should be immobilised for a time, and I cannot construe ” purpose ” in any sense that does not include that state of mind. A person can have two different purposes in doing a particular thing, and even if their reason or motive for doing what they did is called the purpose of influencing public opinion that cannot alter the fact that they had a purpose to immobilise the base. And the statute says ” for any purpose “.

He emphasised that “purpose” includes an immediate intended result, and that additional political objectives or motives do not negate that purpose.

Lord Radcliffe similarly distinguished between direct purpose and motive:

I do not think that the ultimate aims of the Appellants in bringing about this demonstration of obstruction constituted a purpose at all within the meaning of the Act. I think that those aims constituted their motive, the reason why they wanted the demonstration, but they did not qualify the purpose for which they approached or sought to enter the airfield.

He described the appellants’ direct purpose as obstruction of the airfield, which sufficed for the offence if prejudicial.

Lord Devlin treated “purpose” as subjective but covering all anticipated consequences of an act, not just the main or desired objective:

Accordingly, all the results which a man appreciates will probably flow from his act are classifiable as ” purposes” within the meaning of section 1: and since the statute refers to ” any purpose “, the prosecution is entitled to rely on any of them.

He rejected the submission that the immobilisation was only incidental or merely a means to the ultimate aim; the appellants directly intended obstruction as an essential feature of their demonstration.

Lord Pearce considered that “purpose” was used with an objective element: if the purpose was in fact prejudicial, the offence is committed regardless of benevolent motives.

Construction of “safety or interests of the State”

Lord Reid examined the meaning of “State”:

” State ” is not an easy word. It does not mean the Govern- ment or the Executive… And I do not think that it means, as Counsel argued, the individuals who inhabit these islands… Perhaps the country or the realm are as good synonyms as one can find, and I would be prepared to accept the organised community as coming as near to a definition as one can get.

However, he stressed that in matters of defence, the disposition and armament of the armed forces are:

within the exclusive discretion of the Crown and that no one can seek a legal remedy on the ground that such discretion has been wrongly exercised.

Lord Radcliffe underlined that prohibited places are not just information‑sensitive but also to be protected from destruction, obstruction or interference “that would in the result be useful to an enemy”. Saboteurs fall within the Act just as spies do. Interference with a defence airfield was therefore inherently prejudicial when the airfield formed part of the defence system.

Lord Devlin interpreted “State” more precisely in a legal context:

the more precise use of the word ” State “, the use to be expected in a legal context, and the one which I am quite satisfied for reasons which I shall give later was intended in this statute, is to denote the organs of government of a national community. In the United Kingdom, in relation at any rate to the armed forces and to the defence of the realm, that organ is the Crown.

Accordingly, the “interests of the State” are the interests of the State as they are, according to current policy, not as they might or ought to be in political debate:

This statute is concerned with the safety and interests of the State and therefore with the objects of State policy, even though judged sub specie aeternatis that policy may be wrong.

He observed that if a wider meaning were given, “rebels and high‑minded spies” could argue that their treason served the nation’s best interests, an untenable result.

Lord Hodson and Lord Pearce both treated “interests of the State” as necessarily aligned with the policies of the Crown in relation to defence. Lord Pearce said:

In such a context the interests of the State must in my judgment mean the interests of the State according to the policies laid down for it by its recognised organs of government and authority, the policies of the State as they are, not as they ought, in the opinion of a jury, to be. Anything which prejudices those policies is within the meaning of the Act ” prejudicial to the interests of the State “.

Who decides what is prejudicial, and the role of the jury

All members of the House accepted that whether the statutory ingredients of the offence are proved is for the jury, but they defined those ingredients narrowly in this context.

Lord Devlin firmly rejected the suggestion that a judge could direct a verdict:

I cannot accept that the judge is entitled to direct the jury how to answer a question of fact, however obvious he may believe the answer to be and although he may be satisfied that any other answer would be perverse.

However, he held that once it is established that an airfield is part of the defence system and the appellant’s direct purpose is to obstruct its operational use, a verdict of guilty must follow, because such obstruction is necessarily prejudicial to the State’s interests as defined by current defence policy. In that sense, there was little or no room for contrary evidence about policy merits.

Lord Reid considered that, at least where a prohibited place has been declared on the basis that interference “would be useful to an enemy”, the trial judge may properly direct that deliberate interference to a material extent must be treated as prejudicial, and evidence to the contrary may be excluded.

Admissibility of evidence on nuclear policy and risk

The House unanimously upheld the trial judge’s exclusion of evidence about the strategic wisdom or moral propriety of nuclear armament.

Lord Reid stated that allowing such evidence would raise non‑justiciable political questions beyond the proper scope of the criminal process, particularly given Parliament’s evident intention, in 1911, to criminalise deliberate interference with vital defence dispositions irrespective of policy disagreements.

Lord Radcliffe described the proposed evidence—on nuclear devastation, accident risk, radar difficulties and retaliation—as going only to a general issue:

is it prejudicial to the interests of the State to include nuclear armament in its apparatus of defence?

He held that:

I do not think that a court of law can try that issue or, accordingly, can admit evidence upon it.

He noted that such questions depend on “an infinity of considerations, military and diplomatic, technical, psychological and moral” and are not reducible to a triable issue for judge or jury.

Lord Hodson agreed that “evidence upon the policy of the Government in connection with the safety of the State was rightly excluded” and that it would be an “impossible proposition” to invite court and jury to consider whether the siting or existence of particular nuclear aerodromes was in the State’s interests.

Lord Pearce held that the wisdom of possessing nuclear armaments was not relevant, and that allowing a jury to withhold the Act’s protection from prohibited places on policy grounds would undermine the statute.

Lord Devlin distinguished between the Crown’s opinion on what is prejudicial (inadmissible) and evidence about what the Crown’s interests actually are (admissible), which in this case clearly included the effective operation of the airfield.

Royal Prerogative and non‑justiciability of defence policy

Several speeches referred to long‑established principles about the Crown’s prerogative control over the armed forces and defence. Lord Hodson cited the unrepealed recital in 13 Charles II c. 6 affirming that:

the sole supreme government, command and disposition of the militia, and of all forces by sea and land, and of all forts and places of strength is, and by the laws of England ever was, the undoubted right of His Majesty

He and other Law Lords referred to China Navigation Company, Limited v Attorney-General and The Zamora to show that matters of disposition and armament of the forces are within the Crown’s discretion and not subject to judicial review, whether in civil or criminal proceedings.

Lord Devlin, while emphasising that the non‑reviewability of policy decisions limits the issues but does not generally exclude evidence, stressed that in this statute the fact to be proved is a purpose prejudicial to the State’s actual interests, not to what might be its best interests under a different policy.

Implications

The decision establishes that under section 1 of the Official Secrets Act 1911:

• “Purpose” includes any direct, intended consequence of the accused’s conduct—here, immobilising a defence airfield—even if motivated by a long‑term political or moral objective.
• Where a prohibited place forms part of the State’s defence system, deliberate obstruction of its operational effectiveness is, as a matter of law, a purpose prejudicial to the safety or interests of the State, judged by current State policy.
• Benevolent, ideological or political motives, and arguments that alternative defence policies would better serve the true interests of the nation, do not provide a defence and are generally irrelevant save in mitigation.
• Courts and juries are not a forum for testing the wisdom of defence or foreign policy; broad political and strategic debates (such as the merits of nuclear armament) are non‑justiciable in criminal trials under this Act.
• Evidence challenging the foundations of Government defence policy is inadmissible when the statutory issue is whether interference with a defence installation was prejudicial to the State’s interests as presently defined.

The case is a leading authority on the scope of the Official Secrets Act and on the limits of political defences to offences involving sabotage of defence facilities. It also illustrates the interaction between jury trial, executive discretion in national security, and the constitutional principle that courts will not review high‑level defence policy within criminal proceedings.

Verdict: The House of Lords dismissed the appeals and upheld the convictions under section 1 of the Official Secrets Act 1911.

Source: Chandler v DPP [1964] AC 763