Sequential technique for burying an unwelcome report
An inconvenient report is neutralised in escalating steps. First, withhold it 'in the public interest'. If that fails, cast doubt on the evidence ('inconclusive', 'open to other interpretations'), then call the recommendations an insufficient basis for decisions, and finally discredit the author as biased, grudge-bearing or angling for a knighthood or consultancy, so each fallback attacks a different layer: access, data, conclusions, credibility.