This chapter discusses defenses that are particularly relevant to prosecutions involving controlled substance offenses. Specifically, this chapter addresses authorization as a defense to charges brought under Article 7 of the Public Health Code (PHC), MCL 333.7101 et seq.,1 double jeopardy, entrapment, and intoxication as a defense. The “Good Samaritan law” regarding medical assistance that is applicable to MCL 333.7403 (possession) offenses is discussed in Section 2.3. The immunity and affirmative defenses under the Michigan Medical Marihuana Act (MMMA), MCL 333.26421 et seq. and the Medical Marihuana Facilities Licensing Act (MMFLA), MCL 333.27101 et seq. are discussed in Chapter 8.