Article 20 clause (1) provides that no person shall be convicted of any offence except for violation of a law in force at the time of the commission of the act charged as an offence, nor be subjected to a penalty greater than that which might have been inflicted under the law in force at the time of the commission of the offence.
It states that a person can neither be punished for any offence which was at the time of commission not charged as an offence nor be subjected to a penalty greater than that which might have been inflicted under the law in force at the time of the commission of the offence. Hence termed as Ex-Post facto Law.
The said article seeks to safeguard and protect the rights of those persons who are accused of any crime and includes citizens, non- citizens as well as corporations. The significance of the article is evident by stating that the article cannot be suspended even during an emergency declared under article 359.
However, this article needs a beneficial construction in order to ensure the affectivity of the jurisprudence of the said article. In case of beneficial ex post facto law there have been cases where the Indian judiciary has given space to allow the retrospective effect of the law, when the purpose of the Law was to serve to the reformative and rehabilitative need of the accused.
Article 20(1) prohibits the imposition of enhanced penalty or punishment. But it does not bar any reduction in the punishment. In the case of Rattan Lal v. State of Punjab, (AIR 1965 SC 444) the accused a boy of 16 yrs of age was charged against the offence of outraging the modesty of a girl aged 7 years and house trespass. The Magistrate imposed the punishment of rigorous imprisonment of six months and fine. In the meantime the Probation of Offenders Act, 1958 came into force which stated that the person of 21 years of age and below should not generally be sent to the imprisonment. The person accused pleaded to be covered under the reformative theory of the Act. The State contended that the Act in relation was an ex post facto law and could not be applicable in the said case. However, the Apex Court held that an ex post facto law which was beneficial to the accused did not fall under the prohibition laid down under the article 20(1) of the Indian Constitution.
