The Buck Stops with the King

After Yoav’s (Joab) execution, Shlomo (Solomon) refers to Avner and Amasa, both of whom Yoav assassinated against David’s orders, ”And their blood shall return upon the head of Yoav… but upon David… there shall be peace forever from the Lord.” Even though David specifically ordered Yoav not to kill Avner and Amasa, the fact that Yoav did so while under David’s authority meant that David was culpable. I.e., for a king, “The buck stops here.”