Art. 58 Federal Act of October 13, 1965, on the Withholding Tax (WTA)
Art. 58 LIA
If a provisional reduction has been ordered in accordance with Art. 57, para. 3, the cantonal withholding tax office may request the restitution of the tax from the person who benefited from the refund; the right of the canton to claim restitution expires if it is not exercised in the form of a decision within six months following the notification of the provisional reduction.
The decision of the canton on the obligation to restitute can be challenged within thirty days of its notification through an appeal to the cantonal appeals commission; Art. 54 and 56 are applicable.
The provisional reduction lapses if the decision on appeal denies the obligation to restitute; if it admits it in whole or in part, the reduction becomes definitive to that extent.
When, without the consent of the Federal Tax Administration (FTA), the cantonal withholding tax office does not request restitution, or when, in its decision that has entered into force, it has not requested it for the entire amount, the provisional reduction becomes definitive, unless the canton files an action before the Federal Supreme Court within nine months following its notification (Art. 120 of the Act of June 17, 2005, on the Federal Supreme Court).
The decision on restitution made by the cantonal withholding tax office or the cantonal appeals commission is equivalent to an enforceable judgment within the meaning of Art. 80 of the Federal Act of April 11, 1889, on Debt Enforcement and Bankruptcy.