Why Informed Consent?

A wide swath of human activities require informed consent (shorthand for informed, voluntary, and decisionally-capacitated consent), including employment, medical care, medical research, professional relationships, and so forth.

Respect for autonomy and the value placed in liberal societies in allowing the pursuit of rival conceptions of the good life is what underlies this requirement. As Kant famously put it, people should have “freedom to make public use of [their] reason in all matters […] for we are all equipped to reason our way to the good life” (Kant, I. “What is Enlightenment?” Political Writings. Cambridge University Press, 1991).

A central plank of liberal political philosophy is that infringements of autonomy for any reason, such as paternalistic intervention for the agent’s own good, are entirely unacceptable unless they prevent greater harm to others.

But how good are people at reasoning their way to what constitutes “the good life”, to identify the behaviours enabling them to achieve the ends at which they aim, and acting as they themselves believe they ought?

Evidence of Irrationality

In fact, psychology and behavioural economics have accumulated plentiful evidence that our judgement and decision-making are flawed and biased in predictable ways:

We are subject to cognitive biases that limit our ability to assess evidence. We are motivated by incentives but we have a stronger aversion to losses than we have an affinity for gains. Our acts are often powerfully shaped by emotional associations and influenced by subconscious cues. Hyperbolic discounting frequently interferes with our ability to effectively pursue the goals we are setting for ourselves (many believe it plays a role in substance addiction and also explains the obesity epidemic).

In short, the catalogue of cognitive distortions and volitional pathologies is vast and ever-growing. There can be no question of their significant welfare-reducing effects, not only on the lives of individuals, but also on society.

It is not surprising, therefore, that policymakers, employers, insurance companies, researchers, and health-care providers are increasingly interested in the application of various forms of interventions based on psychology and behavioural economics to affect people’s decision-making with respect to health-related behaviours, lifestyles and habits.

Correcting For Biases

Here is an interesting question for professional ethics: Should we also extend the application of such interventions to the informed consent process in order to enhance comprehension or convey information better than what would occur through standard communication?

Should, for example, researchers be allowed to use non-rational interventions to produce changes in the affective states of research subjects in order to manage inflated expectations of benefit (therapeutic overestimation) or conflation of trial participation with care (therapeutic misconception)? Should doctors be allowed to “nudge” their patients to make “better” choices, e.g., use deliberate framing to induce false beliefs in these patients in order to make them choose a medically needed treatment they otherwise would not have chosen?

Those who claim that they should not, argue that such interventions are manipulative rather than respectful of subjects’ autonomy; that they exploit people’s flawed methods of reasoning or decision heuristic; that they elicit irrational rather than rational decision-making, and that they break the bond of trust in the professional-client relationship.

Those who claim that they should be allowed, argue that, as long as they promote the welfare of the subjects and exert their influence without blocking choices or increasing the cost of any of the alternatives, they neither threaten autonomy nor rational decision-making.

Who is right?

A Third Solution?

One simple thought might be: neither. What might be needed is an account of which non-rational interventions do, and which do not, violate the obligation to give subjects a fair opportunity to give autonomous consent. A fundamental problem might be that the analysis of the basic notion of “undue influence” itself is impoverished.

In what way does such influences interfere with autonomous agency and voluntary decision-making? It is difficult to find any shared or well-developed model of such interferences in the ethics literature. What we need is an analysis of this notion that makes explicit its connections with non-autonomous decision-making. Only then can we hope to be able to determine what role, if any, “nudges” and other interventions can legitimately play in enhancing consent and decision-making in the health-care context.


Edmund Henden is a professor at the Centre for the Study of Professions (SPS), where he currently heads the project Autonomy and Manipulation: Enhancing Consent in the Health Care Context.

Photo: Ainar Miyata-Sturm