Hounslow LBC v Twickenham Garden Developments Ltd [1971] Ch 233
EQUITY – MANDATORY INJUNCTIONS WHICH ASSIST A BREACH OF CONTRACT
Facts
A local council had contracted with the defendants for construction work on their land. This contract included a license allowing the defendants to access the land. The council later tried to end the contract, but the defendant claimed the contract was still active and refused to leave. The council sought an interlocutory injunction to remove the defendants from the land.
Issues
Contractual licenses can be revoked at will, but this does not mean that a claimant can necessarily regain possession of their land by themselves without the aid of a court remedy such as an injunction. The issue in this case, was whether the court would grant an interlocutory injunction to expel the defendant from the land.
Decision/Outcome
The court declined to grant an injunction.
Megarry J stated that equity would not assist a party in breaking a contract, even if that contract is not specifically enforceable. The contract here contained an implied term that the license granted would not be revoked, meaning that to grant the injunction would put the council in breach of contract.
The court noted that to grant an injunction with a ‘mandatory’ quality (one which requires positive action) at the interlocutory stage, the court must have a high degree of assurance that the injunction will turn out to have been correctly granted at trial. The council had failed to demonstrate with sufficient certainty that it was entitled to terminate the contract, meaning that there was too great a risk that the injunction would be wrongly granted and equity would have assisted the breach of a contract. For this reason, it would be inappropriate to grant an injunction removing the defendant from the land.
Updated 21 March 2026
This case summary accurately describes the decision in Hounslow LBC v Twickenham Garden Developments Ltd [1971] Ch 233 and the principles Megarry J applied. The core legal principles discussed — that equity will not assist a party in breaking a contract, and that mandatory interlocutory injunctions require a high degree of assurance that they will be justified at trial — remain good law.
Readers should be aware of subsequent developments in the law of interlocutory injunctions generally. The leading test for interlocutory injunctions is now that set out in American Cyanamid Co v Ethicon Ltd [1975] AC 396 (decided after this case), which replaced the older ‘prima facie case’ standard with the ‘serious question to be tried’ threshold. The principle that a higher standard applies to mandatory interlocutory injunctions, as discussed in this case, was affirmed and refined in later authorities including Zockoll Group Ltd v Mercury Communications Ltd [1998] FSR 354 and Nottingham Building Society v Eurodynamics Systems [1993] FSR 468. The law on contractual licences and implied terms preventing revocation has also been developed further since 1971, and students should treat this case as an important but early authority within a broader body of law.
The article is broadly accurate as a summary of the case itself and the reasoning applied, but students should read it alongside more modern authorities on interlocutory injunctions and contractual licences.
