In the UK, a medico-legal defence for a clinician accused of failing to provide an acceptable standard of care for one of his or her qualification and experience. The defence is that a responsible body of medical practitioners would have taken the same action, even though others would have acted differently. The precise size of a responsible body’ has not been defined. The test has been modified following a case referred to as Bolitho, in which it was held that the Bolam defence failed if it could be shown that the actions relied upon, although carried out by some responsible doctors, were nonetheless illogical.