What is the term for a defense that reduces culpability but does not absolve responsibility?

The term that refers to a defense which reduces culpability without completely absolving a person of responsibility is a partial defense. This type of defense acknowledges that while the defendant may have committed the act, there are circumstances that lessen their moral blameworthiness or legal culpability.

In many legal systems, partial defenses can lead to a reduction in charges or punishment. For example, in homicide cases, a partial defense such as provocation can result in the charge being reduced from murder to manslaughter by demonstrating that the defendant's state of mind during the crime was significantly influenced by an external factor.

In contrast, a complete defense would absolve the defendant of all criminal responsibility, while a mitigating factor would usually pertain to factors that could lead to lesser punishment but does not change the culpability or responsibility aspect. An aggravating factor typically works the other way, increasing the severity of the punishment.