P, without using JR, sued D for failing in its statutory duty to provide him with housing. HL found for D, saying that as a general rule it would be contrary to public policy and an abuse of process to allow a person to proceed by way of an ordinary action in order to establish that a public authority's decision had infringed rights entitled to protection under public law. The general rule applied in circumstances where a plaintiff was obliged to impugn a public authority's determination as a condition precedent to enforcing a statutory private law right, as here, and so P ought not proceed by way of private action.
Lord Bridge: the general rule, as set out by Diplock (see above), should apply to cases about whether the PA ought to confer a benefit as much as cases about whether it should deprive someone of a pre-existing benefit. This is because the protection offered by the ordinance/SCA is important here two- namely “the need to obtain leave to apply on the basis of sworn evidence which makes frank disclosure of all relevant facts known to the applicant; the court's discretionary control of both discovery and cross-examination; the capacity of the court to act with the utmost speed when necessary; and the avoidance of the temptation for the court to substitute its own decision of fact for that of the housing authority.”