A regime's legitimacy is the share of its coercive acts that pass the two filters. A government that brakes pollution, fraud, depletion, and systemic risk is using its instrument on the cell the criterion licenses. A government that brakes voluntary trade, productive labour, or peaceful consumption is applying the brake where ΔW_ext ≥ 0 — foot on the brake pedal where it should be off. The criterion gives a verdict per action; summing across a government's portfolio gives a measure of its objective standing to coerce.