420: That’s the average number of court cases per year in which defendants claim that their brains made them commit the crimes for which they are charged. That’s up sharply from 250 per year in 2012, researcher Nita Farahany told Scientific American. Neuroscience most often enters the courtroom in the form of psychological exams or behavioral studies, according to the magazine. But MRIs and CT scans are finding their way into judicial findings more and more often, Farahany’s research found. What was once a last-ditch tactic in death penalty cases is now filtering down through the lesser crimes of the criminal justice system. How courts will handle this complicated, young field of study is an open question.