R v Panel on Take-overs and Mergers, ex p Datafin plc [1987] QB 815

The Panel on Take-overs and Mergers was an unincorporated, self-regulating body without powers directly conferred by statute, yet it exercised decisive influence over takeovers in the City of London. Datafin complained that companies involved in a takeover had breached the City Code and sought review of the Panel's rejection of its complaint. The Panel argued that its authority rested on private agreement and market acceptance, placing its decisions outside public law. In practice, government supported the regulatory system, statutory bodies worked with it, and participants had no realistic choice but to comply with its rulings.

Could the Panel's decisions be judicially reviewed despite its non-statutory and formally private origin, given the public regulatory functions and practical power it exercised?

The Court of Appeal held that the Panel was in principle amenable to judicial review. Sir John Donaldson MR explained that the court should examine both the source and nature of the power. A statutory source strongly indicates public law, but its absence is not conclusive where a body is woven into a governmental regulatory system and performs functions of public importance. The Panel exercised immense de facto power over a field that would otherwise require statutory regulation, and affected participants had no effective contractual remedy. Although jurisdiction existed, the court declined substantive relief on the facts and stressed the need for prompt, restrained intervention in the fast-moving takeover context.

A body may be subject to judicial review even without statutory, prerogative or contractual powers where the nature of its functions, governmental setting and practical authority are sufficiently public. Source remains important, but is not the exclusive test for amenability.

Datafin expanded judicial review beyond conventional governmental bodies and is the starting point for analysing private organisations performing public functions. It does not make every powerful regulator reviewable. Courts consider whether the function is governmental, whether public institutions underpin it, and whether private-law remedies are available. Later cases, including R v Disciplinary Committee of the Jockey Club, ex p Aga Khan, show the limit where authority derives from consensual private arrangements and lacks sufficient governmental integration. The remedy also remains discretionary and sensitive to the regulatory context.