If you tell someone to murder someone else and they do it, are you chayav misa - even if you didn't personally perform the act?
If not, what are you liable for, and on what basis?
This is a discussion in Talmud Kiddushin 43a. Tana Kama and Shammai Hazaken said :
דתני האומר לשלוחו צא הרוג את הנפש הוא חייב ושולחיו פטור שמאי הזקן אומר משום חגי הנביא שולחיו חייב שנא' (שמואל ב יב, ט) אותו הרגת בחרב בני עמון
Now, when it was taught: If he says to his agent, 'Go forth and slay a soul,' the latter is liable, and his sender is exempt. Shammai the Elder said on the authority of Haggai the prophet:(19) His sender is liable, for it is said, thou hast slain him with the sword of the children of Ammon.(20)
The Halacha follows the opposite opinion which see the teller as punished by heaven judgment only.
See Rambam Rotseach 2, 2-3:
2 But a person who hires a murderer to kill a colleague, one who sends his servants and they kill him, one who binds a colleague and leaves him before a lion or the like and the beast kills him, and a person who commits suicide are all considered to be shedders of blood; the sin of bloodshed is upon their hands, and they are liable for death at the hands of God. They are not, however, liable for execution by the court.
3 Which source indicates that this is the law? Genesis 9:6 states: "When a person sheds the blood of a man, by a man his blood shall be shed." This refers to a person who kills a colleague by himself, without employing an agent.
The verse continues: "Of the blood of your own lives I will demand an account." This refers to a person who commits suicide.6
"From the hand of every wild beast will I demand an account" Ibid. 9:5 This refers to a person who places a person before a wild beast so that he will devour him.
"From the hand of a man, from the hand of one's brother, will I demand an account for the soul of a man" ibid.. This refers to a person who hires others to kill a colleague. In all of the three last instances, the verse uses the expression "will I demand an account," indicating that their judgment is in heaven's hands.