If the defendant appeals on facts and law, can the penalty increase?

If an appeal on facts and law is filed solely by the defendant, or by persons acting on the defendant’s behalf, a penalty more severe than the previous penalty may not be imposed.

Even if the amount of the penalty does not increase, can the type of offense change?

Yes, the court may change the legal definition of the offense; the Constitutional Court has ruled that this is consistent with the law.

Was this decision rendered unanimously?

Yes, all members of the Constitutional Court agreed that the decision should be one dismissing the request.

CONSTITUTIONAL COURT RULINGS18 September 2026

Is IT Risky to Challenge Your Penalty?

Official titleConstitutional Court Decision Dated 25/6/2026, E: 2026/71, K: 2026/148

The Constitutional Court has decided that the rule stating that a new judgment rendered in appeals on facts and law filed on behalf of the defendant may not impose a penalty more severe than the previous penalty (the prohibition on adverse amendment) is consistent with the constitution and that the request for annulment is dismissed.

Right Violatednull

Application TypeConcrete-review objection

Details of the Regulation

Şanlıurfa 1. Çocuk Mahkemesi has applied to the Constitutional Court for the annulment of Article 283 of the Code of Criminal Procedure No. 5271 (CMK). The principal reasoning for the objection is that the rule protects the defendant only with respect to the amount of the penalty (final penalty), but does not provide protection against adverse consequences that may arise when the nature of the offense changes, such as execution of the sentence, supervised release, or deprivation of rights.

In its review, the Constitutional Court emphasized that this rule, known as the “prohibition on adverse amendment,” is an important safeguard enabling the defendant to seek relief through legal remedies without fear of being sentenced to a more severe penalty. The Court stated that, within the discretion of the legislature, this safeguard may be confined solely to the “amount of the penalty,” and that the legal characterization of the offense may be changed in accordance with the purpose of establishing the material truth.

It was stated in the decision that the rule in question meets the criteria of certainty and foreseeability, which are requirements of the rule-of-law principle. It was concluded that this legislative provision, which operates in favor of the defendant, does not disturb the reasonable balance between the public interest and the individual benefit; accordingly, the request for annulment was unanimously dismissed on 25 June 2026.

REGAS Commentary

This decision clearly delineates the limits of the “prohibition on adverse correction” in criminal proceedings. Its practical significance for citizens is as follows: When an objection is made solely on behalf of the defendant, the judge may not increase the prison term; however, the judge may change the “name” (characterization) of the offense. Even if the prison term remains the same, this may indirectly affect the conditions for execution of the sentence or the criminal record entry because the type of offense has changed. By ruling that this does not constitute a violation of a constitutional right, the Constitutional Court has upheld the existing practice.

Questions You Might Have

If the defendant appeals on facts and law, can the penalty increase?: If an appeal on facts and law is filed solely by the defendant, or by persons acting on the defendant’s behalf, a penalty more severe than the previous penalty may not be imposed.
Even if the amount of the penalty does not increase, can the type of offense change?: Yes, the court may change the legal definition of the offense; the Constitutional Court has ruled that this is consistent with the law.
Was this decision rendered unanimously?: Yes, all members of the Constitutional Court agreed that the decision should be one dismissing the request.

Key Terms

Aleyhe Değiştirme Yasağı: The rule that, where the lawsuit is appealed on points of law or appeal on facts and law is sought solely on behalf of the defendant, the new judgment may not contain a penalty more severe than the previous penalty.
Suçun Nitelendirilmesi: The determination by the court of which type of offense under the statute the committed act falls within, such as theft or robbery.
İstinaf: A means of having the decisions of courts of first instance reviewed by a higher court in both factual and legal respects.

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