Four Advantages of Bumpy Laws

In prior posts, I expressed a general preference for smooth legal relationships. They often (though not always) lead to laws that better fit our underlying moral theories. Also, smooth legal relationships tend to treat similar cases similarly and may lead to better incentive schemes. (I will simply speak of "smooth laws" to mean laws in which smooth legal relationships predominate or are most salient.)

But let me describe four reasons one might prefer bumpy laws. First, sometimes we have "bumpy needs." A legal determination simply must result in a binary outcome. For example, the Constitution mandates that the U.S. president be at least 35 years old. Nothing magical happens at 35, but it's difficult to smooth the relationship between maturity and eligibility for the presidency. You can't be a little bit president. The same principle often applies to laws that govern the operation of others laws. For example, we generally think a law should be either constitutional or unconstitutional, not 40% constitutional. Ditto for many aspects of evidence law, civil procedure, and more. (We're often too quick to assume that we have bumpy needs, even in the presidency example, but the general point remains.)

Second, bumpy laws will often be cheaper and easier to administer. Smooth laws require us to figure out where an input fell along a spectrum. That's hard and requires considerable factfinding. With bumpy laws, we make the easier determination as to whether an input was above or below some threshold. For example, it's easier to determine whether or not a person was negligent (under our bumpy ordinary negligence laws) than to say how negligent he was across the spectrum of negligence.

Third, bumpy laws more tightly control discretion. For example, statutory minima make the criminal law bumpy. If you reasonably use defensive force to kill a perceived attacker, you leave the courthouse a free person. If you were just slightly unreasonable, in many jursidictions, you will face at least the minimum sentence for murder. This will sometimes be unjust. But, some people think, there are benefits of statutory minima: they restrict judicial discretion and perhaps make sentences more uniform. I can't settle that debate here, except to draw attention to the trade off.

Finally, bumpy laws may sometimes have other advantages in terms of their memorability or in terms of the messages they send. I'm a little bit skeptical here, but I can't rule out the possibility. For example, a bumpy law says there is a $150 fine for exceeding the 65mph speeed limit. A smoother law says there is a fine of $10 per mph driven above the 65mph speed limit. Is one version more memorable than the other? Does one send a better or clearer message than the other? I'm not sure, and I can't entirely rule out such possibilities from an armchair.

To sum up, then, while smooth laws will often better suit our underlying theories, such benefits need to be weighed against our need for binary outcomes, the cost and administrability of smooth laws, the ways smooth laws may fail to appropriately allocate discretion, and the possible advantage (or disadvantage) bumpy laws may have with respect to memorability and the expressive force of law. But it would be foolish to simply assume that the law is as smooth as it should be. After all, many jurisdictions with a history of using contributory negligence principles in tort switched in recent decades to smoother, comparative negligence principles. If you think such a change was for the better, why assume that we have already rooted out the law's excessive bumpiness?