INTRODUCTION

The dwindling supply of organs for organ transplants is sometimes attributed to the use of motorcycle helmets, of all things. Head injuries to helmetless riders are often fatal, but leave the riders' otherwise healthy organs intact, thus making the riders perfect organ donation candidates. Helmets, which, by standard estimates, reduce motorcycle fatalities by a remarkable 39 percent (Norvell and Cummings 2002), have appeared to reduce the number of organ donors as a consequence. The estimates that we report later suggest that the elements of constitutional design have almost as dramatic an effect on constitutional mortality. It may be that, like its effect on organ donations, decreased mortality leads to similar downstream unintended consequences for constitutions (as our normative discussion in Chapter Two indicates). But, we do not concern ourselves with that matter here. Our goal in this chapter is to describe and report the findings from our analysis regarding the mortality of constitutions over the last 200 years. In particular, our purpose is to test the hypotheses specified in the previous chapter.

Our focus is on hypotheses having to do with the design of constitutions, as opposed to their environment. Because we are interested in understanding the impact of design over and above that of the environment, we are obliged to specify and measure the consequences of an inclusive set of environmental factors. Doing so pays the analytic dividends of controlling for such effects, but also can be enlightening in its own right.