Who judged whether Britain could exceed treaty tonnage?

What authority decided whether Britain had to destroy five serviceable cruisers or could exceed the London treaty limits?

There was no tribunal; invoking the relevant article depended on each government's judgment and good faith, supported in Britain by advice from the Crown's law officers.

Churchill asked what authority could decide whether Britain had to destroy five cruisers or could invoke the treaty article permitting additional tonnage. The minister replied that no international tribunal existed for that purpose. Each government relied on its own judgment and good faith, while Britain's Crown law officers advised on legal interpretation. That arrangement made compliance depend on national decisions rather than a binding external ruling. The exchange also bears on C-class cruisers that might still have useful service lives after conversion for anti-aircraft work. The minister was Thomas Inskip, whose later Inskip Award returned control of the Fleet Air Arm to the Royal Navy.