P sought judicial review of D’s decision to reduce the deployment of police officers to help exporters against protestors. HL denied the claim, but see the ratio relating to the test to be applied:
Lord Slynn: In determining whether the public law duty to protect lawful activity had been fulfilled, the correct approach in examining the new arrangement of the Chief Constable was to ask “whether the steps taken were proportionate…the distinction between the two tests [proportionality and Wednesbury unreasonableness] in practice is in any event much less than is sometimes suggested. The cautious way in which the European Court usually applies this test, recognising the importance of respecting the national authority's margin of appreciation, may mean that whichever test is adopted, and even allowing for a difference in onus, the result is the same.”
Lord Cooke: He says that it is “unfortunate” that Lord Greene MR’s test set out in Wednesbury has become a basis of judicial review. He says that although this does not resolve all the problems of that test, it is better to phrase it simply by asking “whether the decision in question was one which a reasonable authority could reach.” He also says that often proportionality + margin of appreciation will produce the same result as Wednesbury unreasonableness. These points indicate that he wishes to enable the “reasonableness” test to go beyond merely that which is “manifestly absurd”.