Yesterday the Colorado Supreme Court overturned a death sentence for a man convicted of kidnapping, rape, and murder because the jurors consulted the Bible while deliberating over the penalty. Although the jurors were urged, per state law, to make an "individual moral assessment," the Supreme Court concluded the Bible was an inappropriate outside influence. It's hard to see how thumbing through the Bible would make an otherwise just result improper. Unless there is evidence of corruption or bad faith, respect for jurors' independence should preclude an inquiry into the source of the moral values they bring to bear in making their decisions. (Surely biblical wisdom often plays a role–acknowledged or not, read from the text or recalled from memory–in death penalty deliberations.)
As The New York Times notes in its story on the ruling, consulting the Bible does not necessarily favor the prosecution. The defense in this case urged the jurors to show mercy "as God ultimately took mercy on Abraham." Although the point is valid, I'm hazy on the specific reference. Abraham himself is known for his merciful instincts (as when he urges God to spare the city of Sodom), but I don't recall that he ever murdered anyone, or even committed a sin so grave that forgiving him for it could be considered a model of mercy (unless passing his wife off as his sister counts). Wouldn't "as God ultimately took mercy on Cain" have made more sense?