The teller has a heart attack in the process, the death. Under these facts the perpetrator could be criminally convicted of murder. In a criminal or civil trial it is usually the duty of the jury to determine the truth and weight of all facts in controversy. A fact finder is not allowed to determine issues of law. This is reserved only for the judge.
Fact finders are usually the men and women of a jury.
The intent can be proved by showing the killing was planned or was part of a scheme. It can also be the result of a death committed in the commission of a dangerous felony. The specific elements for first degree murder and their variations are established by statute in each state. The crime of unlawfully taking possession of a house or structure by the use of force or threat of force. The goal of the expert is to assist the fact finder in understanding scientific information.