## Facts

- Government Communications Headquarters (GCHQ) is a signals-intelligence and communications-security agency.
- For years, GCHQ staff were encouraged to join national trade unions, and management followed a consistent practice of consulting unions on employment conditions.
- In December 1983, the Minister for the Civil Service, acting under a Civil Service Order in Council made under the royal prerogative, directed that GCHQ employees could not belong to national trade unions and could join only an internal staff association approved by GCHQ’s director.
- The change was implemented without prior consultation with the unions and was justified by the government as necessary for national security, citing prior industrial action at GCHQ.
- The unions and affected employees sought judicial review, arguing that the established consultation practice created a legitimate expectation that consultation would occur before such a change.
- The trial court found procedural unfairness and invalidated the instruction; the appellate court reversed on the ground that national security made the matter non-justiciable.

## Issues

1. Whether an instruction made under the royal prerogative is, in principle, subject to judicial review.
2. Whether a consistent prior practice of consulting unions created a legitimate expectation requiring consultation as a matter of procedural fairness.
3. Whether national security justified dispensing with consultation and limited the court’s ability to grant relief.

## Decision

- The House of Lords held that exercises of prerogative power are not immune from judicial review; review turns on the nature and subject matter of the power, not its formal source.
- The House of Lords accepted that the longstanding consultation practice could create a legitimate expectation of consultation, and absent countervailing considerations the failure to consult would generally be procedurally improper.
- The House of Lords dismissed the appeal because national security considerations justified proceeding without consultation in the circumstances.

## Legal Principles

- Administrative action is generally reviewable on public law grounds of illegality, irrationality, and procedural impropriety; these grounds apply to prerogative powers as well as statutory powers where rights or legitimate expectations are affected.
- A public authority’s established, consistent practice can generate a procedural legitimate expectation that the practice will be followed unless there is a sufficient justification for departure.
- Some categories of executive decision-making (including matters closely connected to national security and similar high policy areas) may be non-justiciable or subject to strong judicial restraint.
- Where national security is credibly invoked, courts may examine whether the claim is bona fide, but they will ordinarily not substitute their assessment for the executive’s judgment on the security risk; a genuine security justification can defeat procedural fairness claims that would otherwise succeed.

## Conclusion

The House of Lords confirmed that prerogative powers are generally amenable to judicial review and recognized that a settled consultation practice can create a legitimate expectation of consultation, but it denied relief because national security provided a sufficient justification for the government’s non-consultation and decision to restrict trade union membership at GCHQ.


Council of Civil Service Unions v. Minister for the Civil Service, [1984] 3 All E.R. 935 (H.L.)