In Nasib Singh v. State of Punjab (2022) 2 SCC 89, the Supreme Court laid down the following principles:
(i) Section 218 provides that separate trials shall be conducted for distinct offences alleged to be committed by a person. Sections 219 – 221 provide exceptions to this general rule. If a person falls under these exceptions, then a joint trial for the offences which a person is charged with may be conducted. Similarly, under Section 223, a joint trial may be held for persons charged with different offences if any of the clauses in the provision are separately or on a combination satisfied;
(ii) While applying the principles enunciated in Sections 218 – 223 on conducting joint and separate trials, the trial court should apply a two-pronged test, namely, (i) whether conducting a joint/separate trial will prejudice the defence of the accused; and/or (ii) whether conducting a joint/separate trial would cause judicial delay.
(iii) The possibility of conducting a joint trial will have to be determined at the beginning of the trial and not after the trial based on the result of the trial. The Appellate Court may determine the validity of the argument that there ought to have been a separate/joint trial only based on whether the trial had prejudiced the right of accused or the prosecutrix;
(iv) Since the provisions which engraft an exception use the phrase ‘may’ with reference to conducting a joint trial, a separate trial is usually not contrary to law even if a joint trial could be conducted, unless proven to cause a miscarriage of justice; and
(v) A conviction or acquittal of the accused cannot be set aside on the mere ground that there was a possibility of a joint or a separate trial. To set aside the order of conviction or acquittal, it must be proved that the rights of the parties were prejudiced because of the joint or separate trial, as the case may be.