Some crimes require the prosecution to prove that the defendant caused a particular result. Proving this fact is usually not difficult. However, challenging issues of causation sometimes occur in the criminal law, most frequently in homicide cases because homicide requires the prosecutor to prove the defendant caused the death of another human being. (See Chapter 8.)
Causation often can be established by showing that the defendant's action directly brought about the resulting harm. In most cases causation is simply a question of physical occurrence. Did the defendant initiate physical forces that, according to the laws of nature, led to a particular result?