Lord Advocate v Dumbarton District Council  2 AC 580
Established that the rule for disregarding a statute where it contradicted royal prerogative was not a test of whether the statute was in the public benefit.
The Ministry of Defence wished to improve the defences of their perimeter fencing at a nuclear submarine base located in Faslane. To do this, the MOD marked off the road that ran in parallel with the base, however they did so without the permission of the local regional council (Strathclyde) or district council (Dumbarton), as required by statute. As the MOD had not satisfied the statutory requirements for cutting off some road, the district council issued an order to remove the diversion. Subsequently, the MOD applied for judicial review of the orders against their signs, submitting they did not apply to the MOD as an emanation of the royal prerogative.
Was the MOD immune from Court orders on the grounds that their authority derived from the royal prerogative.
Initially the Courts found for the MOJ, however upon appeal the House of Lords overturned this decision, asserting the immunity principle whereby the judiciary ought not distinguish between various forms of the Crown’s actions in relation to statute as such an analysis would be problematic. Subsequently, the Crown was either bound by statute or not and an analysis of other factors is unnecessary.
Thus, where there is a conflict apparent between a statute and the royal prerogative, the rule for not applying the Act does not turn on whether the statute was passed with the public benefit in mind.