The concept of "mistake" as a defense in criminal law is based on the principle that a person should not be held criminally liable for actions taken under a genuine and reasonable mistake of fact. The Bharatiya Nyaya Sanhita, 2023 (BNS), addresses this under various sections, mainly focusing on acts done by individuals who genuinely believe themselves to be justified by law.

Relevant Sections under BNS

Several sections under BNS address the concept of "mistake" as a defense. We will elaborate on these sections with explanations, examples, and relevant case law.

Section 14 Act Done by a Person Bound by Law or Mistaken Belief

Section 14: Good Faith Protection

Section 14 shields individuals who, in good faith, believe they are bound by law to perform a certain act. The essence of this provision is to protect people from criminal liability when they act under the impression that they are legally obligated to do so.

• Example: If a police officer arrests a person under the mistaken belief that they are a criminal due to a faulty identification process, the officer can be protected under Section 14 if they acted in good faith, believing they were carrying out their duty.
• Illustration: A customs officer seized goods from a passenger, mistakenly believing that the goods are contraband based on misleading information. Here, the officer would be protected under Section 14 because they acted under a mistaken belief of fulfilling their duty.
• Relevant Case Law:
  • State of Orissa v. Ram Bahadur Thapa (1961): The Supreme Court of India emphasized that a person can be protected under this section if the act was done under a genuine belief that the law required it.

Section 17: Act Done by a Person Justified, or by Mistake of Fact Believing Himself, Justified by Law

This section exempts individuals from liability if they commit an act under a genuine mistake of fact, believing themselves to be justified by law. The key here is the distinction between a mistake of fact (exempted) and a mistake of law (not exempted).

• Example: A person apprehends someone, believing them to be a thief based on incorrect information, but later it turns out the individual was innocent. If the person acted in good faith under the mistaken belief that the suspect was committing a crime, Section 17 can apply.
• Illustration: If a shopkeeper sees someone running away with goods and mistakenly believes they are stolen, the shopkeeper can stop and apprehend the person. If it later turns out that the person had already paid for the goods, the shopkeeper's actions are still protected under Section 17 due to a mistake of fact.
• Relevant Case Law:
  • R v. Tolson (1889): Although a British case, the principle from this judgment was that a reasonable mistake of fact could be used as a defense in criminal cases. It has been referenced in Indian law to explain the concept of "mistake of fact."

Key Legal Principle: Mistake of Fact vs. Mistake of Law

• Mistake of Fact: A factual error leading to the belief that an act was justified (e.g., mistaking a real gun for a toy).
• Mistake of Law: Misunderstanding or ignorance of the law, which generally does not provide a defense (e.g., not knowing that theft is illegal).

Ignorantia juris non excusat is a Latin phrase that means "ignorance of the law excuses no one". The legal principle under BNS aligns with the global doctrine where a mistake of fact can exempt an individual from criminal liability, whereas a mistake of law does not, as ignorance of the law is no excuse.

Illustrations from Supreme Court Judgments:

1. State of Maharashtra v. Mayer Hans George (1965): The Supreme Court held that a person who brought gold into India under the mistaken belief that he had declared it properly could not use this as a defense. This was treated as a mistake of law, not a mistake of fact.
2. Kartar Singh v. State of Punjab (1994): The Supreme Court acknowledged that individuals might commit acts under a mistake of fact, which can be excused if they genuinely believed they were following legal directives. This ruling reinforced the application of sections like Section 14 and Section 17 of BNS.

Landmark Case: R v. Prince (1875)

While this is a British case, its principles have been influential. In R v. Prince, the defendant was charged with taking a girl under 16 out of the possession of her father. The defendant mistakenly believed the girl was over 16. The court held that his mistake regarding the girl's age (a mistake of fact) did not absolve him because the act itself was inherently wrongful. The principle here has shaped Indian legal thinking about when a mistake of fact may or may not be a defense.

Application of Mistake Defense: Real World Scenario

Consider a scenario where an individual is caught with an object resembling a banned weapon. They argue that they believed it was a harmless replica. If they can prove that their belief was reasonable, and they acted in good faith, they may be excused from criminal liability under the general exceptions provided by BNS.

Conclusion:
The general exceptions under BNS, especially those related to mistakes, play a critical role in protecting individuals who act under genuine, good faith beliefs. These provisions ensure that only those with clear intent to violate the law or with knowledge of their wrongful actions face criminal charges.