diminished capacity
noun /dɪˌmɪnɪʃt kəˈpæsəti/
/dɪˌmɪnɪʃt kəˈpæsəti/
(North American English) (British English diminished responsibility)
[uncountable] (law)- a state in which a person who is accused of a crime is not considered to be responsible for their actions, because they are mentally ill