Void for Vagueness

When law regulates a profession, where does it get its standards? Largely from the profession. Members of professions acquire esoteric and abstract knowledge through formal education and the experience of practice. They use professional judgment in applying this knowledge to each case. Because legislatures and courts lack this expertise, they adopt the standards of the experts. Thus in a malpractice suit, juries are instructed to determine whether the doctor met medicine's standard of care. Furthermore, physicians must be called as expert witnesses to guide juries in that work.

Even when lawmakers contemplated intensifying their regulation of medicine by creating the duty of informed consent, they could consult a literature to which doctors and medical ethicists contributed crucially. In some jurisdictions, even the scope of the duty is determined by using the medical standard of disclosure (although in other jurisdictions the standard is the degree of disclosure sufficient to permit the ordinary patient to make a sound decision).

Nor have lawmakers striven to extend the reach of informed consent beyond the norms of medicine. They might have done so in two ways. First, they might have broadened the legal standard of disclosure. This seems to have happened only sporadically and tentatively. Second, fact-finders (juries and trial-court judges) might have interpreted the legal standard as demanding elaborate or unusual disclosures. This too has apparently not much happened. Indeed, plaintiffs rarely bring informed consent actions (except as appendages to malpractice suits), rarely win them, and rarely obtain large verdicts.

In short, lawmakers have essentially established rules intended to hold medicine to its own standards and then mostly left the system to work unmolested. What lawmakers have not noticed, however, is that the status of informed consent in the medical literature has become parlous. Two developments particularly matter. First, a torrent of empirical evidence now suggests that informed consent does not work as intended: Doctors generally tell patients too little and patients generally understand too little for patients to make the choices that lawmakers had imagined.

Second (and relatedly?), the literature seems to be deserting the term "informed consent." And what instead? A comet shower of novel terms. "[T]here is now a profusion of competing models that attempt to convey subtle differences in the sharing of information and power between clinician and patient."¹ A smattering of the latest models: "evidence-based patient choice," "informed decision-making," "informed medical decision-making," "informed treatment decision-making," "physician as perfect agent," "shared decision-making," "shared clinical decision-making," "shared medical decision-making," and "shared treatment decision-making." From this welter of multiplying, mystifying distinctions, one term has emerged most stoutly—"shared decision-making."

So, what is shared decision-making? Would that I knew. Or that anyone did. Makoul and Clayman heroically slogged through the literature and concluded that "there is no shared definition of shared decision making." They "identified 31 separate concepts used to explicate SDM, only two of which appeared in more than half of the conceptual definitions." In fact, "60% of articles that purport to focus on shared decision-making failed to include any conceptual definition at all."²

As this suggests, many proponents of shared decision-making seem to regard its meaning as self-evident. And no doubt most people suppose that they understand the term. "Sharing" does the real rhetorical work here. Who doesn't understand sharing? Who could oppose it? Yet the skimpiest reflection reveals that the slogan is ambiguous unto incoherence.

For example, what makes a decision "shared"? It is logical, plausible, reasonable to say, as many advocates of shared decision-making seem to say, that anyone who helps shape a decision, helps give the decision meaning, helps give it effect, "shares" in it. But on this reading, virtually all consequential medical decisions are shared. The doctor must propose something; the patient must at least acquiesce; both have participated; they have shared the decision.

Or look at "sharing" from another angle. When doctors and patients talk, they develop a framework for their conversation and goals for their interaction. These often emerge implicitly, with neither party really grasping what is happening. Both parties shape the framework and assumptions: Patients initially...