It is generally believed that while in some cases government should intervene to protect people from risk—by imposing air safety standards, for example—in other cases, such as mountain climbing, the onus should be on the individual to protect himself or herself. In the eyes of the public at large, the demarcation between the two kinds of cases has mainly to do with whether the risk in question is incurred voluntarily. This distinction between voluntary and involuntary risk may in fact be the chief difference between lay and expert judgments about risk. Policy experts tend to focus on aggregate lives at stake; laypeople care a great deal whether a risk is undertaken voluntarily. However, judgments about whether a risk is "involuntary" often stem from confusion and selective attention, and the real reason for such judgments frequently lies in an antecedent judgment of some other kind. They are thus of little utility in guiding policy decisions.

First, it is not easy to determine when a risk is voluntarily incurred. Although voluntariness may be entirely absent in the case of an unforeseeable collision with an asteroid, with most environmental, occupational, and other social risks, it is not an all-or-nothing matter, but rather one of degree. Risks incurred by airline passengers are typically thought to be involuntary, since passengers have no control over whether a plane is going to crash. But they can choose airlines on the basis of safety records or choose not to fly. In characterizing the risks as involuntary, people focus on a small part of a complex interaction, not the decision to fly, but the accident when it occurs.

Second, people often characterize risks as "voluntary" when they do not approve of the purpose for which people run the risks. It is unlikely that people would want to pour enormous taxpayer resources into lowering the risks associated with skydiving, even if the ratio of dollars spent to lives saved were quite good. By contrast, people would probably not object to spending enormous resources on improving the safety of firefighters, even though the decision to become a firefighter is voluntary. In short, there is no special magic in notions like "voluntary" and "involuntary." Therefore, regulatory policy should be guided by a better understanding of the factors that underlie judgments about voluntariness.

In general, the government should attempt to save as many lives as it can, subject to the limited public and private resources devoted to risk reduction. Departures from this principle should be justified not by invoking the allegedly voluntary or involuntary nature of a particular risk, but rather by identifying the more specific considerations for which notions of voluntariness serve as proxies.