Bible Verses About Murder: To be proved by two witnesses at least

Whoso killeth any person, the murderer shall be slain at the mouth of witnesses: but one witness shall not testify against any person that he die.

But if any man hate his neighbor, and lie in wait for him, and rise up against him, and smite him mortally so that he dieth, and he flee into one of these cities;

One witness shall not rise up against a man for any iniquity, or for any sin, in any sin that he sinneth: at the mouth of two witnesses, or at the mouth of three witnesses, shall a matter be established.