Which of the following defenses is not considered valid in criminal cases?

Voluntary intoxication is generally not considered a valid defense in criminal cases because individuals are typically held responsible for their actions when they voluntarily choose to consume intoxicating substances. The legal principle is that people should be accountable for the consequences of their decisions, including the decision to consume alcohol or drugs, which may impair their judgment.

In contrast, self-defense, involuntary intoxication, and insanity can serve as valid defenses in certain circumstances. Self-defense is recognized when an individual uses reasonable force to protect themselves from imminent harm. Involuntary intoxication occurs when a person is unable to control their substance intake, often due to coercion or deception, and can be used to argue that the individual did not possess the intent necessary to commit a crime. Insanity defenses assert that a person was unable to understand the nature of their actions due to severe mental illness at the time of the offense, which can absolve them of legal responsibility.

By understanding the distinctions between these defenses, individuals can see why voluntary intoxication does not hold the same legal weight in criminal proceedings.