A conviction based solely on uncorroborated hearsay evidence from a single witness, without independent corroboration or proper investigation, does not prove guilt beyond reasonable doubt and constitutes a gross irregularity. While section 269 of the Criminal Procedure and Evidence Act permits conviction on the evidence of a single competent and credible witness, courts must exercise extreme caution, particularly in serious offences, and should not be content with single witness testimony when other witnesses who could provide corroboration are available but not called. Hearsay evidence cannot form the primary basis for conviction when the original source of the information could have been called to testify. Where crucial witnesses (such as alleged eyewitnesses to the transaction) are not called and no explanation is given for their absence, and where key evidence (such as phone records, photographs, or agreements) mentioned in testimony is not produced, the prosecution fails to prove its case beyond reasonable doubt. The benefit of the doubt must go to the accused where the State's evidence consists of contradictory and uncorroborated testimony from a suspect witness.