David Jaros’s thought-provoking new Article, Perfecting Criminal Markets, sheds light on a heretofore unappreciated effect of our obsession with criminalization: that merely by creating new crimes, lawmakers may inadvertently strengthen existing criminal markets. To support his argument, Jaros adopts the tenets of neoclassical deterrence theory, which assume that criminalizing an activity will deter its occurrence. But the model Jaros employs has its limits. The weakness of a rational choice account of criminal markets is that it relies so heavily on the assumption that prospective criminals will be aware of, and swayed by, criminal laws that might in fact be quite obscure. In the first Part of this Response, I consider some of the factors,...