The behavior of the offender after the commission of a crime may consist, inter alia, in confession of the offense. In criminal law, the confession of a criminal offense, under certain conditions, can constitute a mitigating circumstance in terms of sentencing. In order for the confession to the offense to be constituted as a mitigating factor in sentencing, it must be voluntary, complete and truthful, and that it contributes to establishing the relevant facts in the proceedings. The Criminal Code of the Republic of Serbia does not recognise the confession to a crime as an independent factor in sentencing, but it is evaluated through the offender's 'conduct after the commission of the offense and particularly his attitude towards the victim of the offense', while in several of its provisions the Criminal Procedure Code of the Republic of Serbia mentions the confession of a defendant. In our theory of criminal law, the generally prevailing view is that any confession to an offense does not constitute a mitigating circumstance, while, on the other hand, in practice, almost any confession to criminal offenses is uncritically accepted and erroneously evaluated as a mitigating circumstance in sentencing. The paper presents several examples where the courts incorrectly evaluated the confession to a criminal offense as a mitigating circumstance, and it particularly points to the fact that the courts' rationale does not contain the reasons for which confession was viewed as a mitigating circumstance.