This week, we're looking at the science of the ultimate criminal punishment. Pharmacologist and science writer David Kroll joins us to discuss the chemistry of the drugs used in lethal injections. We'll talk to law professor Samuel Gross, editor of the National Registry of Exonerations, about the rates of false convictions in death penalty cases. And we'll speak to Johns Hopkins University psychiatrist Dr. James Harris about the complex issues at the intersection of capital punishment and intellectual disability.