substantial capacity test
substantial capacity testA legal test for defining a person as “insane” under the law, which the court will accept if it finds that the defendant had a mental defect such that he or she lacked the substantial capacity to either:
(1) appreciate the wrongfulness of his or her conduct; or
(2) conform his or her conduct to the law.
The substantial capacity test combines elements of the M’Naughten test and the irresistible impulse test.