Federal Supreme Court, 29.07.2026, 6B_878/2025
Facts
A.________ had correctly affixed a motorway vignette to their vehicle's windshield. It subsequently peeled off almost entirely on its own, without being damaged. In order to keep it on the same vehicle, they reattached it using double-sided adhesive tape and then permanent glue. They claimed they only intended to fix the vignette securely and were unaware that its spontaneous detachment rendered it invalid. However, they were aware that a vignette could not be tampered with for the purpose of being used on multiple vehicles. (consid. 4.4)
On September 3, 2024, the Aargau Obergericht found A.________ guilty of falsifying official stamps and sentenced them to a suspended monetary penalty of 20 daily rates of CHF 70 each, as well as a fine of CHF 300. Upon an initial appeal, the Federal Supreme Court set aside this decision on June 25, 2025, and remanded the case for a new decision (6B_863/2024). On September 24, 2025, the Obergericht nevertheless handed down the same conviction again. A.________ therefore appealed to the Federal Supreme Court a second time. (consid. A-D)
Law
Falsification of official stamps within the meaning ofArt. 245 SCC requires, from a subjective standpoint, that the perpetrator acts intentionally. They must be aware that they are falsifying or altering an official stamp, or using an already invalidated stamp as valid, and must intend to use it as if it were authentic or intact. Dolus eventualis is sufficient when the perpetrator foresees the commission of the offense as possible and accepts it. What the perpetrator knew, intended, or accepted is a matter of fact, whereas the legal classification of these elements as intent is a matter of law. (consid. 3.2.1-3.2.2)
According toArt. 13 para. 1 SCC, a person who acts under the influence of a mistaken view of the facts is judged according to that view if it is favorable to them. A mistake of fact may relate not only to a descriptive element of the offense but also to a normative element. A false understanding regarding the legal classification of a factual element can thus exclude intent. If the mistake could have been avoided by exercising the required care, the perpetrator is only punishable for negligence if the offense in question also penalizes that form of commission. (consid. 4.2.1-4.2.2)
When a case is remanded by the Federal Supreme Court, the cantonal authority is bound by the reasoning of the remand judgment. It may not modify facts that have been definitively established nor re-examine issues that were not the subject of the remand. The new proceedings are limited to the elements whose re-examination is necessary to comply with the binding reasoning of the Federal Supreme Court. (consid. 3.5)
Application to the specific case
The High Court had reasoned that, as an experienced driver, A.________ should have known that a detached sticker could not simply be reattached using unauthorized methods. It also held that he should have been aware of the sticker's security features and that his ignorance of the instructions on the backing could not constitute a mistake of fact. (consid. 3.3)
The Federal Supreme Court noted, however, that this was not the typical case where a sticker is intentionally tampered with before its first use to allow for reuse on multiple vehicles. The sticker had been correctly applied and then detached spontaneously without damage. A.________ had consistently maintained that he was unaware that it became invalid simply because of this, and that his only intention was to reattach it securely to the same vehicle. (consid. 4.4)
A.________ was therefore laboring under a mistake of fact regarding a normative element of the offense: he knew that tampering intended to allow for the reuse of a sticker was prohibited, but he was unaware that the sticker had legally "lost its value" the moment it detached spontaneously and thus no longer constituted a valid official stamp. By dismissing his statements as mere defensive assertions based, in particular, on media reports concerning different situations, the cantonal authority acted arbitrarily. It should have acknowledged the existence of a mistake of fact within the meaning of Art. 13 of the Swiss Criminal Code. (consid. 4.4)
It was irrelevant whether A.________ could have avoided this mistake, for instance by reading the instructions on the sticker's backing. Under Art. 13 para. 2 of the Swiss Criminal Code, an avoidable mistake only allows for a conviction for negligence if the offense in question is also punishable in that form. However, Art. 245 of the Swiss Criminal Code does not criminalize forgery by negligence. The mistake therefore excluded the intent required to commit the offense. (consid. 4.4)
The Federal Supreme Court further observed that the High Court had violated the binding nature of the remand judgment by altering the facts regarding the method used to reattach the sticker. The first federal judgment had definitively established the use of double-sided adhesive tape followed by permanent glue. The remand concerned only the subjective element of the offense and the existence of a potential mistake. The cantonal authority could not, therefore, adopt a different version of the facts regarding the objective element during the second proceeding. (consid. 3.5)
Outcome
The appeal is granted to the extent that it is admissible, and A.________ is acquitted of the charge of forgery of official stamps under Art. 245 ch. 1 of the Swiss Criminal Code. His mistake regarding the invalidation of the detached sticker constitutes a mistake of fact under Art. 13 of the Swiss Criminal Code, which excludes intent, and a conviction for negligence is not possible. The case is remanded to the Aargau High Court solely for a new decision on the costs and legal fees of the cantonal proceedings. No federal court costs are charged, and the Canton of Aargau must pay A.________ CHF 3,000 in legal fees for the proceedings before the Federal Supreme Court. (consid. 4.5; disp. 1-3)