Actus reus refers to the act or omission that comprise the physical elements of a crime as required by statute. Actus reus includes only a voluntary affirmative act, or an omission (failure to act), causing a criminally proscribed result.
...criminal act
(Wex page)
Aggravating circumstances refers to the factors that increase the severity or culpability of a criminal act. Typically, the presence of an aggravating circumstance will lead to a harsher penalty for a convicted criminal.
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