Unsatisfactory Evidence

A lawyer was questioning the testimony of a witness to a shooting.
"Did you see the shot fired?"
"No sir, I only heard it."
"Stand down," said the judge sharply. "Your testimony is of no value."
The witness turned around in the box to leave, and when his back was turned to the judge he laughed loudly and derisively.
Irate at this exhibition of contempt, the judge called the witness back to the chair and demanded to know how he dared to laugh at the court.
"Did you see me laugh, Judge?" asked the witness.
"No, but I heard you," retorted the judge.
"That evidence is not satisfactory, Your Honour," said the witness respectfully .