Butler's practice in the beginning was chiefly in the defence of criminals, or in civil cases where persons of that class were parties. There was very likely to be a dramatic scene in court when he was for the defence. His method of defence was frequently almost as objectionable as the crime he was defending. He attacked the character of honest witnesses, and of respectable persons, victims of his guilty clients, who were seeking the remedy of the law. He had many ingenious fashions of confusing or browbeating witnesses, and sometimes of misleading juries. He once asked a medical expert who undertook to testify about human anatomy, in a case of physical injury, this question: "State the origin and insertion of all the muscles of the forearm and hand from the elbow to the tips of the fingers"; and another, "Give a list of the names and the positions of all the bones in the body." This was something like asking a man who claimed to know the English language to give off hand all the words of the English language beginning with a. But it confused a worthy and respectable country doctor, and misled the jury. The best citizen of a country village, or his wife or daughter, who had to testify against a thief or burglar who had broken into a house had to encounter his ruffianly treatment on the witness stand. So Butler became a terror, not to evil-doers but to the opponents of evil-doers throughout the county of Middlesex. Few lawyers liked to encounter his rough speech and his ugly personalities.