Deuteronomy 17:7

Kill him. Thus testifying that they approve the sentence, and are willing that his blood should be required at their hands, if they had accused him falsely. The criminal was hurled down a precipice by one of the witnesses, and, if he survived, he was stoned by the other, and by the whole people. Maimonides asserts, that the execution took place on some great festival, for the terror and instruction of the multitude; but others call this in question. (Fagius) (Calmet)