The doctrine of informed consent has deeper historical roots in the practice of law than in the practice of medicine. The modern rule that medical treatment cannot be given without the informed consent of competent patients did not arise until the late twentieth century, whereas a century earlier, courts already recognized that, like other agents, lawyers may breach their fiduciary duty to client-principals when they fail to provide them with sufficient information. In some respects, however, the legal profession may have lagged behind the medical profession. Thus lawyers, who played a critical role in developing the informed consent model in medicine, have been criticized for failing to adequately develop such a model for their own practice.

The legal profession has long recognized that lawyers may not reveal confidential information or represent conflicting interests unless the client...