Chapter 4 delves into the various defenses to criminal liability, categorizing them into justifications, excuses, and procedural defenses. Justification defenses, such as self-defense, defense of others, and defense of property, acknowledge the act but argue it was warranted under the circumstances to prevent greater harm. Excuse defenses, including insanity, intoxication, infancy, duress, and mistake, recognize that certain conditions impair an individual's ability to form criminal intent or control their actions, making full accountability unjust. Procedural defenses like entrapment, statute of limitations, and double jeopardy focus on the fairness and integrity of the legal process, protecting individuals from government overreach, outdated prosecutions, and multiple trials for the same offense. Understanding these defenses is crucial for legal practitioners and individuals navigating the criminal justice system, ensuring that justice is served in a balanced and equitable manner.