Del. Code 11, § 422 : Crimes And Criminal Procedure — Defenses To Criminal Liability — Intoxication not mental illness Date: 2 Sep 2016 TEXT PDF Current through 2016 Legislative Session, Act 399 Evidence of voluntary intoxication shall not be admissible for the purpose of proving the existence of mental illness, mental defect, serious mental disorder or psychiatric disorder within the meaning of § 401 of this title. Del. C. § 422 11 Del. C. 1953, § 422; 58 Del. Laws, c. 497, § 1; 71 Del. Laws, c. 153, § 1; 78 Del. Laws, c. 224, § 10.;