Mitigating circumstances

surrounding events which make a situation less severe

In law, extenuating circumstances are criminal cases in which, though an offence has been committed without legal justification or excuse, its gravity, from the point of view of punishment or moral opprobrium, is mitigated or reduced by reason of unusual or extreme facts leading up to or attending the commission of the offence.
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These are facts that, while not negating an offence or wrongful action, tend to show that the defendant may have had some grounds for acting the way he/she did. - (read more on Mitigating circumstances)