A medical practitioner's role as adviser prior to treatment is crucial in providing the basis on which the patient consents to a procedure or not. In Sidaway v Board of Governors of the Bethlem Royal Hospital and the Maudsley Hospital [1985] A.C. 871, the House of Lords confirmed the applicability of the “Bolam” test, historically the province of treatment cases, to cases concerning the disclosure of risks. By a majority decision, although without a clear ratio, the question of what risks a practitioner should disclose was regarded as matter for clinical judgment. Where a practitioner could demonstrate that he had disclosed an amount of information that was in keeping with the practice of a responsible body of medical opinion, this would defeat a claim in negligence. Lord Bridge provided two exceptions: first where there was a substantial risk of grave adverse consequences, an example of which he gave as the 10% risk of a stroke, and, secondly, where the patient had specifically questioned the practitioner. In both circumstances, the risk ought to be disclosed regardless of settled medical practice. Lord Scarman dissented on the basis that the analytical starting point in disclosure cases was the patient's right to know what risks they would be subjected to; this was not a matter for clinical judgment.