Key legal question
Whether the CHF 50,000 debt-interest allowance under Art. 33(1)(a) DBG must be doubled for jointly taxed spouses.
Extracted holding
No. The allowance is granted once per jointly assessed tax unit, not separately to each spouse.
Extracted reasoning
The wording of Art. 33(1)(a) DBG contains no spouse-based doubling, unlike other provisions. A joint assessment also allows cross-offsetting of excess deductions, preserving the scheme's simplicity.