If insanity and duress can excuse criminal behavior, why can’t social and economic distress affect culpability? The theory that environmental deprivation or a “rotten social background” should excuse criminal liability has been widely discussed. Some research indicates that growing up in impoverished, unstable, and violent environments can affect moral judgment—implicating the M’Naghten test—or other attributes such as self-control—perhaps implicating the irresistible impulse test. Nevertheless, the idea of an environmental deprivation excuse remains highly controversial, and there are many distinctions between insanity and environmental deprivation. As you read the following passages, consider both the similarities and the differences between environmental deprivation and the excuses we have studied. Remember, too, that criminal law is partly moral, and partly instrumental. What would be the practical effects of recognizing an environmental deprivation defense?