Final answer:
In Macbeth, it is the murderers who are officially blamed for Banquo's death. Macbeth hired them to secure his position as king, but he never admits his involvement publicly.
Step-by-step explanation:
Macbeth has officially blamed the murderers for the death of Banquo. These murderers were hired by Macbeth himself to ensure Banquo would not be a threat to his newly acquired throne, as predicted by the witches. Despite Macbeth's involvement, he never publicly admits to his role in Banquo's murder but rather places the blame on the paid assassins, distancing himself from the act.