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HMRC internal manual

Business Income Manual

Specific deductions: crime (expenditure involving): blackmail and extortion: no criminal intent necessary

For a payment to be disallowed as induced by blackmail or extortion, there is no requirement for any criminal intention or criminal act on the part of the payer - the blackmail victim. It is sufficient that the expenditure was induced by a criminal threat. That threat itself will be a criminal act on the part of the blackmailer or extortionist but the payer will be doing no more than succumbing, willingly or not, to the pressure of the threat.