Protection in respect of conviction for offences
Quick Summary (TL;DR)
The Ironclad Criminal Justice Shield: Protects every person against Ex-Post Facto criminal laws, Double Jeopardy (being punished twice for the same offence), and Forced Self-Incrimination (custodial confessions). Cannot be suspended even during a National Emergency.
In Simple Citizen Words
Article 20 is the citizen's unbreakable shield against police coercion and retroactive state tyranny. Along with Article 21, it is so sacred that under the 44th Constitutional Amendment (Article 359), it CANNOT be suspended even during wartime or a National Emergency. It consists of three distinct constitutional pillars:
1. Article 20(1) — Protection against Ex-Post Facto Criminal Laws: No person can be convicted of an act that was not a crime at the time it was committed, nor can they be subjected to a penalty greater than what was prescribed when the act took place.
2. Article 20(2) — Protection against Double Jeopardy (Nemo debet bis vexari): No person shall be prosecuted and punished for the same offence more than once by a court of law.
3. Article 20(3) — Immunity from Self-Incrimination: 'No person accused of any offence shall be compelled to be a witness against himself.' This makes police torture, forced signatures on blank papers, and involuntary narco-analysis or polygraph tests completely unconstitutional.
1. Article 20(1) — Protection against Ex-Post Facto Criminal Laws: No person can be convicted of an act that was not a crime at the time it was committed, nor can they be subjected to a penalty greater than what was prescribed when the act took place.
2. Article 20(2) — Protection against Double Jeopardy (Nemo debet bis vexari): No person shall be prosecuted and punished for the same offence more than once by a court of law.
3. Article 20(3) — Immunity from Self-Incrimination: 'No person accused of any offence shall be compelled to be a witness against himself.' This makes police torture, forced signatures on blank papers, and involuntary narco-analysis or polygraph tests completely unconstitutional.
What Rights You Have
Absolute immunity from being convicted under a criminal law enacted after the event (Art 20(1))
Benefit of reduced punishment: if a law later reduces the sentence for an offence, the accused gets the benefit of the lighter penalty (Rattan Lal ruling)
Protection from being prosecuted and punished twice for the same criminal offence (Art 20(2))
Constitutional Right to Remain Silent during police interrogation regarding self-incriminating questions (Art 20(3))
Police confessions are inadmissible: any confession made to a police officer in custody has zero evidentiary value (Sec 25 Evidence Act / Sec 23 BSA)
Protection against forced signing of blank papers or confession statements inside a police lockup
Absolute ban on involuntary Narco-analysis, Polygraph (lie-detector), and Brain-Mapping tests without judicial consent (Selvi ruling)
Non-derogable status: Article 20 protections remain 100% active even during a National Emergency (Art 359)
Exceptions & Reasonable Restrictions
Article 20(1) bars retroactive criminal laws, not retroactive civil or tax laws. Article 20(2) does not bar departmental/disciplinary suspension alongside a criminal trial. Under Article 20(3), physical samples (fingerprints, handwriting, DNA, blood tests under statutory law) are considered physical evidence rather than "testimonial compulsion".
Why This Matters in Daily Life
If a police officer threatens to beat you unless you sign a confession paper in the lockup, Article 20(3) renders that forced confession worthless in court and makes the coercion unconstitutional.
Want deeper legal & historical context? Explore the official Bare Act or Supreme Court Precedents & CAD Debates: