An 'inquisition' (or inquiry) held before a Justice of the Peace was the primary instrument for management of lunacy in eighteenth-century England. Yet its purpose was to protect wealth rather than the individual. The 1766 case book of Dr John Monro, London's leading doctor for madness, unexpectedly records a consultation that links two siblings who both had inquisitions. Nicholas Jeffreys' only son was attested lunatic in 1744: to circumvent inheritance through primogeniture, Jeffreys directed the family wealth to his last living child. One of his three daughters married Lord Camden, a former Lord Chancellor: after her and her second sister's deaths, the last-surviving sister was also placed under inquisition in 1780, to ensure the inheritance for his own family.