Deuteronomy 17:6

Overview - Deuteronomy 17
The things sacrificed must be sound.
Idolaters must be slain.
Hard controversies are to be determined by the priests and judges.
12 The contemner of that determination must die.
14 The election;
16 and duty of a king.
Treasury of Scripture Knowledge

Deuteronomy 17:6  (King James Version)
At the mouth of two witnesses, or three witnesses, shall he that is worthy of death be put to death; but at the mouth of one witness he shall not be put to death.

19:15 Numbers 35:30 ; Matthew 18:16 ; John 8:17 John 8:18 ; 2 Corinthians 13:1 ; 1 Timothy 5:19
Hebrews 10:28