Numbers 35 NASB
'If anyone kills a person, the murderer shall be put to death at the evidence of witnesses, but no person shall be put to death on the testimony of one witness.
Deuteronomy 17:6-7 NASB
On the evidence of two witnesses or three witnesses, he who is to die shall be put to death; he shall not be put to death on the evidence of one witness. The hand of the witnesses shall be first against him to put him to death, and afterward the hand of all the people. So you shall purge the evil from your midst.
In the above texts it seems only the cases involving a death sentence warranted that there be two or three witnesses
Was it standard procedure the issue of two or three witnesses or it only applied where a death sentence was involved?