The Murder of the Litchfield father is presented as a crime Margaret Litchfield was led to commit under Stephen Norton’s psychological influence. The revelation changes the meaning of her act: she had imagined herself delivering her sisters from imprisonment, but Hercule Poirot places responsibility for the pattern of manipulation on Norton, the trusted family friend who cultivated that belief.

Background and Motive

Norton’s influence worked by reinforcing impulses and convictions already present, rather than by directly instructing someone to kill. In Margaret’s case, he was a friend of the Litchfields; in conversation with him, she came to regard herself as a heroine who could free her sisters from a life sentence of confinement. Poirot doubts that Margaret would have acted as she did without Norton’s influence.

The episode belongs to a wider pattern Poirot traces among Norton’s victims. He describes Norton as seeking out people in whom some susceptible idea or desire was already present, then applying psychological pressure until it could overcome their resistance. The Litchfield crime is thus not framed as an isolated family decision, but as one instance of Norton’s repeated method.

Revelation and Responsibility

The truth reaches the reader through Poirot’s account to Arthur Hastings. He identifies the family friend responsible for shaping the crime as Stephen Norton, whose reassuring public character concealed his role as an instigator. Poirot calls him “honest Iago,” invoking the contrast between a trusted appearance and covert responsibility.

That account distinguishes Margaret’s action from its cause without claiming that she did not kill her father. Poirot’s explanation is that Norton cultivated her belief that the murder would rescue her sisters; the daughter, rather than the manipulator, had borne the apparent guilt. The revelation recasts the crime as psychological manipulation operating through a family relationship and an imagined act of liberation.

Elizabeth Cole and the Aftermath

Poirot asks Hastings to find Elizabeth Cole, who is also Elizabeth Litchfield, and either let her read his account or tell her what it contains. Elizabeth has continued to believe that her sister Margaret killed their father. Poirot wants Hastings to tell her that her father was killed not by his daughter but by the sympathetic family friend Stephen Norton.

The purpose of that message is to release Elizabeth from the belief that she is tainted by her family’s crime. Poirot argues that she should not refuse life on that account, and makes Hastings responsible for carrying the explanation to her. The crime’s aftermath therefore continues beyond the death itself: Elizabeth’s understanding of her sister, her father, and her own place in the family depends on whether the concealed influence is finally disclosed.