Justice Rehnquist's concurrence in Mullaney v. Wilbur noted that its existe
Justice Rehnquist's concurrence in Mullaney v. Wilbur noted that its existence "bears no necessary relationship to" required elements of a crime, and Justice Harlan warned against its application in Davis v. U.S.  In Leland v. Oregon, the Supreme Court found no Due Process violation in requiring it be proven beyond a reasonable doubt, while the Supreme Court upheld the Mott rule, restricting its admission in Clark v. Arizona.  In 1984, Congress eliminated the "substantial capacity test" in favor of the common law McNaughton "right from wrong" test, and forbade courts from taking into account voluntary substance abuse when considering it in an act passed in reaction to the acquittal of John Hinckley.  For 10 points, name this phenomenon in which a criminal defendant can avoid conviction by showing his defective mind was incapable of forming criminal intent.
Justice Rehnquist's concurrence in Mullaney v. Wilbur noted that its existence "bears no necessary relationship to" required elements of a crime, and Justice Harlan warned against its application in Davis v. U.S.  
insanity defense [accept obvious equivalents; do not accept "negating mens rea"]