To be convicted of a crime in the United States, a person must be proven guilty “beyond a reasonable doubt.” But what is reasonable doubt? Even sophisticated legal experts find this fundamental doctrine difficult to explain. In this accessible book, James Q. Whitman digs deep into the history of the law and discovers that we have lost sight of the original purpose of “reasonable doubt.” It was not originally a legal rule at all, he shows, but a theological one.The rule as we understand it today is intended to protect the accused. But Whitman traces its history back through centuries of Christian theology and common-law history to reveal that the original concern was to protect the souls of jurors. In Christian tradition, a person who experienced doubt yet convicted an innocent defendant was guilty of a mortal sin. Jurors fearful for their own souls were reassured that they were safe, as long as their doubts were not “reasonable.” Today, the old rule of reasonable doubt survives, but it has been turned to different purposes. The result is confusion for jurors, and a serious moral challenge for our system of justice.

To be convicted of a crime in the United States, a person must be proven guilty “beyond a reasonable doubt.” But what is reasonable doubt? Even sophisticated legal experts find this fundamental doctrine difficult to explain. In this accessible book, James Q. Whitman digs deep into the history of the law and discovers that we have lost sight of the original purpose of “reasonable doubt.” It was not originally a legal rule at all, he shows, but a theological one. The rule as we understand it today is intended to protect the accused. But Whitman traces its history back through centuries of Christian theology and common-law history to reveal that the original concern was to protect the souls of jurors. In Christian tradition, a person who experienced doubt yet convicted an innocent defendant was guilty of a mortal sin. Jurors fearful for their own souls were reassured that they were safe, as long as their doubts were not “reasonable.” Today, the old rule of reasonable doubt survives, but it has been turned to different purposes. The result is confusion for jurors, and a serious moral challenge for our system of justice.

One of America's leading appeal lawyers, Alan Dershowitz was the man chosen to prepare the appeal should O.J. Simpson have been convicted. Now Professor Dershowitz uses this case to examine the larger issues and to identify the social forces - media, money, gender, and race - that shape the criminal-justice system in America today. How could one of the longest trials in the history of America's judicial system produce a verdict after only hours of jury deliberation? Was this really a case of circumstantial evidence?