When he volunteered for the Scopes trial, Clarence Darrow was already known as a brilliant and controversial defense attorney. He built a national reputation defending labor radicals and accused murderers and fighting the death penalty. The following excerpt, from one of Darrow’s speeches before the court on the second day of the trial, displays his characteristic wit in analyzing the legal consequences of the Butler Act.

Let’s see now. Can your Honor tell what is given as the origin of man as shown in the Bible? Is there any human being who can tell us? There are two conflicting accounts in the first two chapters. There are scattered all through it various acts and ideas, but to pass that up for the sake of argument, no teacher in any school in the state of Tennessee can know that he is violating a law, but must test every one of its doctrines by the Bible, must he not? . . .

[The law] does not specify what you cannot teach, but says you cannot teach anything that conflicts with the Bible. Then just imagine making a criminal code that is so uncertain and impossible that every man must be sure that he has read everything in the Bible and not only read it but understands it, or he might violate the criminal code. Who is the chief mogul that can tell us what the Bible means? He or they should write a book and make it plain and distinct, so we would know. Let us look at it. There are in America at least 500 different sects or churches, all of which quarrel with each other over the importance and nonimportance of certain things or the construction of certain passages. All along the line they do not agree among themselves and cannot agree among themselves. They never have and probably never will. There is a great division between the Catholics and the Protestants. There is such a disagreement that my client, who is a schoolteacher, not only must know the subject he is teaching, but he must know everything about the Bible in reference to evolution. And he must be sure that he expresses his right or else some fellow will come along here, more ignorant perhaps than he and say, “You made a bad guess and I think you have committed a crime.” No criminal statute can rest that way.

Source: Clarence Darrow, Speech in Defense of Religious Liberty, in The World’s Most Famous Court Trial: Tennessee Evolution Case (1925; reprint, Dayton, TN: Rhea County Historical Society, 1978).