Being acquitted or convicted once protects you from ever being tried again for anything connected to that incident.

The section allows a later trial for a genuinely different offence, for example if new consequences like the victim's death appear afterward, or if the earlier court wasn't competent to try that particular offence, so it is not an absolute bar in every situation.

Bharatiya Nagarik Suraksha Sanhita, 2023

Section 337

Person once convicted or acquitted not to be tried for same offence

(1) A person who has once been tried by a Court of competent jurisdiction for an offence and convicted or acquitted of such offence shall, while such conviction or acquittal remains in force, not be liable to be tried again for the same offence, nor on the same facts for any other offence for which a different charge from the one made against him might have been made under sub-section (1) of section 244, or for which he might have been convicted under sub-section (2) thereof.§

(2) A person acquitted or convicted of any offence may be afterwards tried, with the consent of the State Government, for any distinct offence for which a separate charge might have been made against him at the former trial under sub-section (1) of section 243.§

(3) A person convicted of any offence constituted by any act causing consequences which, together with such act, constituted a different offence from that of which he was convicted, may be afterwards tried for such last-mentioned offence, if the consequences had not happened, or were not known to the Court to have happened, at the time when he was convicted.§

(4) A person acquitted or convicted of any offence constituted by any acts may, notwithstanding such acquittal or conviction, be subsequently charged with, and tried for, any other offence constituted by the same acts which he may have committed if the Court by which he was first tried was not competent to try the offence with which he is subsequently charged.§

(5) A person discharged under section 281 shall not be tried again for the same offence except with the consent of the Court by which he was discharged or of any other Court to which the first-mentioned Court is subordinate.§

(6) Nothing in this section shall affect the provisions of section 26 of the General Clauses Act, 1897§

(10 of 1897) or of section 208 of this Sanhita. Explanation.—The dismissal of a complaint, or the discharge of the accused, is not an acquittal for the purposes of this section. Illustrations.§

(a) A is tried upon a charge of theft as a servant and acquitted. He cannot afterwards, while the acquittal remains in force, be charged with theft as a servant, or, upon the same facts, with theft simply, or with criminal breach of trust.§

(b) A is tried for causing grievous hurt and convicted. The person injured afterwards dies. A may be tried again for culpable homicide.§

(c) A is charged before the Court of Session and convicted of the culpable homicide of B. A may not afterwards be tried on the same facts for the murder of B.§

(d) A is charged by a Magistrate of the first class with, and convicted by him of, voluntarily causing hurt to B. A may not afterwards be tried for voluntarily causing grievous hurt to B on the same facts, unless the case comes within sub-section (3) of this section.§

(e) A is charged by a Magistrate of the second class with, and convicted by him of, theft of property from the person of B. A may subsequently be charged with, and tried for, robbery on the same facts.§

(f) A, B and C are charged by a Magistrate of the first class with, and convicted by him of, robbing D. A, B and C may afterwards be charged with, and tried for, dacoity on the same facts.§

Why this exists

This provision, from Section 300 of the old CrPC, implements the constitutional protection in Article 20(2) of the Constitution of India (no person shall be prosecuted and punished for the same offence more than once) along with the common-law principles known as autrefois acquit and autrefois convict. It gives finality to criminal verdicts and protects individuals from being harassed through repeated prosecutions over the same conduct, while carving out narrow exceptions where genuinely new offences or later-discovered consequences come to light.

How courts read it

Indian courts have generally read this protection narrowly, insisting that the offence and its essential ingredients must truly be identical, or that a fresh trial must genuinely involve new facts or consequences, before the bar against a second trial applies. In State of Bombay v. S. L. Apte, the Supreme Court examined when offences under different statutes arising from the same facts are not treated as the 'same offence' for this purpose, holding that a second prosecution is permissible where the ingredients of the two offences differ, even if both arise from a common set of facts.

Common misconceptions

Myth: Being acquitted or convicted once protects you from ever being tried again for anything connected to that incident.
Fact: The section allows a later trial for a genuinely different offence, for example if new consequences like the victim's death appear afterward, or if the earlier court wasn't competent to try that particular offence, so it is not an absolute bar in every situation.