The farce of the Brexit “impact assessments” tells voters everything they need to know

As the satire which occasionally passes for the Brexit negotiations builds up to the fevered will-they-won’t-they climax of the December European Council summit, it is worth paying some attention to its no less farcical but somewhat more legalistic subplot: the long-running saga of the government’s sectoral “impact assessments.”

These papers supposedly examine the impact of European Union withdrawal across the British economy—from aviation to textiles, architecture to road haulage. Millions of livelihoods stand to be affected by…