Deuteronomy 17:5-7
5 take the man or woman who has done this evil deed to your city gate and stone that person to death.
6 On the testimony of two or three witnesses a man shall be put to death, but no one shall be put to death on the testimony of only one witness.
7 The hands of the witnesses must be the first in putting him to death, and then the hands of all the people. You must purge the evil from among you.