Swiss Federal Supreme Court, 13.01.2026, 9C_715/2025
Facts
A taxpayer was notified of a tax reassessment decision and a fine for the 2010 to 2016 tax periods, covering cantonal and municipal taxes as well as direct federal tax. Their objection (Einsprache) was rejected.
The taxpayer subsequently appealed this decision to an incompetent authority, the Tax Appeals Tribunal of the Canton of Zurich, which dismissed the case and did not forward the appeal to the competent authority. The taxpayer then petitioned the Administrative Court of the Canton of Zurich, requesting an extension of the appeal deadline. The Administrative Court first confirmed in an interlocutory decision that the authority incorrectly seized had no obligation to forward the case. Then, in the contested judgment, it rejected the request for an extension of the deadline and, consequently, did not address the merits of the tax dispute. The taxpayer filed a public law appeal with the Federal Supreme Court against this final decision of non-admissibility.
Legal Analysis
The Federal Supreme Court reiterates the requirements for the substantiation of an appeal underArt. 42 para. 1 and 2 of the Federal Supreme Court Act (FSCA). The appellant must concisely explain how the contested act violates the law. The reasoning must be contained within the appeal document itself; a mere reference to other submissions or case files is insufficient.
The appellant must address the grounds of the contested decision and demonstrate, point by point, how the lower authority violated the law. Purely appellatory criticism is not sufficient. Stricter requirements apply to the violation of fundamental rights (Art. 106 para. 2 FSCA). When an appeal is directed against a decision of non-admissibility, the appellant must specifically explain why the lower court should have admitted the case.
Application to the present case
The Federal Supreme Court finds that the appeal clearly fails to meet the substantiation requirements.
Firstly, the appellant largely limits themselves to referring to previous submissions, which is inadmissible.
Secondly, their claim regarding the violation of the right to be heard (Art. 29 para. 2 of the Federal Constitution) is not sufficiently substantiated. They claim not to have had the opportunity to comment on the extension of the deadline following a previous interlocutory decision by the Federal Supreme Court, but they do not explain why this decision should have triggered a new deadline or why the Administrative Court should have waited for further observations from them.
Thirdly, and decisively, the appellant does not engage in any discussion with the reasoning of the contested judgment. They do not explain how the Administrative Court's refusal to grant an extension of the appeal deadline and its decision of non-admissibility were contrary to the law or arbitrary.
As the appeal does not contain sufficient grounds, it is deemed manifestly inadmissible.
Outcome
The Federal Supreme Court will not hear the appeal. The legal costs are to be borne by the appellant.
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