Professor Berman yesterday links to the recent 9th Circuit opinion in U.S. v. Mitchell, affirming the death penalty sentence for a defendant involved in a double murder. As the opinion notes, during the sentencing phase, Mitchell offered this mitigating evidence:

The defense presented as mitigating evidence the testimony of family members, friends, and teachers of Mitchell whom they portrayed as an excellent high school student with no disciplinary problems except for a brief suspension for possessing marijuana, who was an outstanding athlete with college football prospects, a leader both in student council and in sports, and respectful towards teachers. (p. 11560)

According to Wiggins v. Smith, defendants have a right to introduce psychologically mitigating evidence, including descriptions of child abuse, neglect, and other unfortunate social factors in determining the appropriateness of a death sentence. In Mitchell, of course, it's the opposite: Mitchell introduced evidence of his relatively uneventful childhood as proof of his good character. Considering Justice Steven's dissent in the recent case Schriro v. Landrigan suggesting that antisocial personality disorder is an "organic brain syndrome" akin to delirium or mental retardation one wonders what constitutes a psychologically relevant aggravating factor in death penalty cases.

Of course defendants are entitled to present mitigating evidence during trial and sentencing. Such evidence should include salient psychological factors that could impinge on culpability. Yet the reduction of character evidence, psychologically speaking, into exclusively mitigating evidence seems the trend in our criminal justice system these days. This course follows the emergent and popular claim by many scholars that biology is destiny -- and that biology always seems to show a lack of choice by defendants to conform their behavior to the criminal code. Yet such claims should be viewed with a healthy dose of skepticism. As I discuss in this brief essay, history is a great teacher and history is replete with examples of scientific claims once viewed as promising and certain only to be viewed by future generations as downright foolish. Our legal traditions have always placed a great burden upon defendants wishing to exculpate or mitigate their guilt based on psychological factors alone since our system also cherishes individual choice and autonomy. But with choice and autonomy comes responsibility. Few predispositions, childhood histories, and other misfortunes should arguably negate that responsibility given the breathtaking implications such a course would have for our criminal code.