1.1 Facts of the Case
See BGE 149 II 442, dated October 3, 2023
Anna and Benjamin are a married couple living in the city of Zurich. They have been married since 2002 and remain legally and de facto married.
They received a final tax assessment for the 2018 tax period.
In 2021, Anna and Benjamin filed a request with the Zurich Cantonal Tax Office (“KStA ZH”) to have their joint liability for the tax debts from the 2018 tax period lifted. The tax liabilities amount to approximately CHF 270,000. As grounds for the waiver, the spouses argue that the tax liabilities are primarily attributable to Benjamin’s income. Today, Benjamin’s monthly (pension) income amounts to only about CHF 8,000, and he has assets totaling merely about CHF 4,000. Benjamin is therefore unable to settle the tax liabilities for which he is liable. Anna should therefore be released from joint and several liability.
Additional information:
Anna and Benjamin’s marital assets total CHF 450,000. In 2021, Anna receives a monthly pension income of approximately CHF 3,300.
1.2 Questions
- In principle, how are spouses liable for income and wealth taxes?
- When does a spouse’s insolvency result in the termination of joint liability?
- Who bears the burden of proving insolvency?
- At what point must the insolvency be asserted?
- How would you assess the present case involving Anna and Benjamin?
2. Facts of the Case
See Federal Supreme Court 2C_770/2016, 2C_771/2016, dated September 26, 2016
The spouses Casimir and Daniela lived in Schaffhausen from 2005 to 2007. At the end of 2011, the marriage was legally and de facto dissolved.
In 2013, the Schaffhausen State Tax Office (KStA SH) initiated a back-tax assessment procedure for the tax years 2005–2007. Daniela had entered into a trust agreement with her uncle, who lived in Germany. Based on this agreement, she had received, in trust, a share in Elster AG, which in turn enabled her to serve on the board of directors of Elster AG. From 2005 to 2007, Daniela received income from Elster AG that was not justified for business purposes (benefits in kind amounting to approximately CHF 12,000 per year), which she had not declared.
Only Casimir challenged the back-tax assessment all the way to the Federal Supreme Court, arguing, among other things, that the benefits in kind were attributable not to Daniela but to her uncle. The Federal Supreme Court dismissed Casimir’s appeal and upheld the assessments issued by the Schaffhausen Cantonal Tax Office (KStA SH) for the tax periods 2005–2007.
Questions
- Is Casimir, in principle, jointly and severally liable for the back taxes for 2005–2007?
- Can Casimir assert the waiver of joint liability in the present case (in SH)? What procedural considerations must Casimir take into account?
- Could Casimir assert the waiver of joint liability in this case if he and Daniela had been residents of the canton of AR from 2005 to 2007?
- When is there a de facto or legal separation of the spouses?
- How is the respective share of the total tax (direct federal tax) calculated that Casimir must pay for the 2005 tax period if joint and several liability is waived?
Additional Information on the Facts:
[Spouses’ income in 2005 (in CHF):
- Casimir’s salary (net) 100,000
- Daniela’s salary (net) 50,000
- Income from Elster AG paid to Daniela 12,000
Spouses’ deductions for 2005 (in CHF):
Casimir’s business expenses 4,000
](<#footnote-ref-1>)- Married couple deduction 2,000
[The spouses’ taxable income for 2005 is therefore CHF 142,700 (162,000 – 19,300).
It is further assumed that the spouses’ total federal tax, including back taxes for 2005, amounts to CHF 10,000.
3. Facts of the Case
See Federal Supreme Court 9C_653/2025 dated February 3, 2026
The spouses Frances (lawyer, MLaw) and Gérard (Federal Certificate in Finance and Accounting, employed by a bank) reside in Geneva. In 2024, the Geneva Tax Administration (KStA GE) issued penalty notices to the spouses for completed tax evasion for the tax periods 2014–2018.
In the tax returns they jointly filed and signed for the 2014–2018 tax periods, Frances and Gérard had failed to declare life insurance policies they held with a foreign company and the income derived from them. The policies were held in equal shares by Frances and Gérard. The GE Tax Office had learned of the life insurance policies through the automatic exchange of information. Following an appeal by the spouses, the GE Tax Office reduced the fine in its appeal decision from 0.75 times to 0.5 times the amount of the evaded taxes. The GE Tax Office considered that Frances and Gérard had acted negligently rather than intentionally.
Frances and Gérard had challenged the fine decisions all the way to the Federal Supreme Court, arguing, among other things, that they were subject to a mistake of fact (Art. 13 of the Swiss Criminal Code [StGB, SR 311.0]) and a mistake regarding the law (Art. 21 StGB): They had relied on information provided by a client advisor at the foreign bank—which had brokered the insurance policies—stating that the insurance policies would be taxed abroad. The Federal Supreme Court upheld the fine orders. Given Frances’s legal training and Gérard’s work in banking, the two should have exercised greater caution or should have known that foreign authorities are not competent to provide information regarding Swiss tax law. Merely relying on the information provided by the foreign private bank was therefore negligent.
Questions
- What is the procedural status of spouses in tax law (ordinary tax proceedings)?
- Does the principle of joint liability between spouses (joint taxation for income and wealth tax) also apply in criminal tax proceedings?
- Scenario 1: How would the GE Public Prosecutor’s Office (KStA GE) likely have assessed the case if the life insurance policies were solely in Gérard’s name, but Frances had co-signed the tax return?
3.1 Scenario 2:
Both Frances and Gérard have each taken out life insurance policies in their own names. Gérard is responsible for filing the spouses’ tax return. He declares his life insurance policy but omits Frances’s. Frances does not review the tax return and signs it “blindly.”
Question
How would the GE State Tax Office likely have assessed the case in this scenario?
3.2 Scenario 3:
Both Frances and Gérard have each taken out life insurance policies in their own names. Gérard is responsible for filing the couple’s tax return. He declares his life insurance policy but omits Frances’s. Frances does not sign the tax return even after the KStA GE granted an extension.
Question
How would the GE State Tax Office likely have assessed the case in this scenario?
4. Facts
See Federal Supreme Court 9C_308/2024, 9C_309/2024 dated December 4, 2024
The spouses Hans and Iris reside in the canton of TG. They are shareholders and managing directors of Jezebel AG, which is headquartered in SG. For years, Kurt, a trustee, has been handling Jezebel AG’s bookkeeping as well as the tax returns (both the corporation’s tax return and the spouses’ personal tax returns). On Kurt’s advice, in 2015 and 2016, the couple’s personal expenses (including home furnishings, consumer electronics, airfare, the notary’s fee for drafting the marriage and inheritance agreement, and a designer handbag) were recorded as business-related expenses at Jezebel AG. The corresponding monetary benefits were not reported as income in the joint tax return.
On July 31, 2018, the auditor for Jezebel AG at the St. Gallen Cantonal Tax Office (KStA SG) calculates the monetary benefits for the 2015 and 2016 tax periods and submits a corresponding report to the Federal Tax Administration (ESTV) and the Thurgau Cantonal Tax Office (KStA TG).
On August 31, 2018, Hans and Iris jointly file a voluntary disclosure with the TG State Tax Office regarding tax evasion. At this point, Hans and Iris have already received final tax assessments for their 2015 and 2016 income and wealth taxes (date of the assessment notices: June 30, 2017). They cooperate fully with the authorities, accept the additional taxes assessed for 2015 and 2016, and pay them in full.
Questions
- Did the voluntary disclosure result in the spouses being exempt from criminal penalties?
- Variation: At Christmas 2017, Iris meets her niece Laura, who is a certified tax expert. Iris proudly tells Laura about the “tax trick” that Kurt taught her and Hans. Laura explains to Iris the possible tax and criminal consequences of the “trick” and strongly advises her to file a voluntary disclosure. When asked about it, Hans refuses to file a voluntary disclosure: he and Iris already pay enough taxes as it is—the tax authorities should figure out the evasion on their own, if they’re going to. Iris, however, is no longer comfortable with the situation, which is why she files a voluntary disclosure with the TG State Tax Authority on December 31, 2017—that is, before the SG State Tax Authority’s audit of Jezebel AG. What are the consequences of the voluntary disclosure for Iris and Hans?
- Digression 1: Are Kurt and Jezebel AG liable to prosecution?
- Side Note 2: What are the withholding tax implications for Jezebel AG, Hans, and Iris?
5. Facts of the Case
The spouses Martina (net salary of CHF 200,000) and Nik (part-time employment, CHF 20,000) are married and live together under the ordinary matrimonial property regime of participation in accrued gains. Martina has a securities account in her name worth CHF 2 million from an inheritance (income: CHF 50,000 per year). Both spouses’ salaries are deposited into a joint account. Years ago, the couple purchased a painting together without formalizing the ownership arrangement.
In December 2031—shortly before the switch to individual taxation—Martina transfers half of the securities account to Nik. The two do not agree to anything in writing; Martina says, “It’s staying in the family anyway, and if we get divorced, I’ll take it back.”
For the 2032 tax year, following the introduction of individual taxation, Martina and Nik each file their own tax return for the first time. Martina fills out both returns; Nik submits his without reading it. It omits the income from the portion of the investment account transferred to him in 2031.
From their joint tax assessments through 2031, there is an outstanding tax liability of CHF 10,000, which is primarily attributable to Nik’s income. Nik becomes insolvent in 2033. That same year—with their marriage now in crisis—Martina requests access to Nik’s 2032 tax return from the tax office.
Questions
- Can the cantonal tax office hold Martina liable in 2033 for the outstanding CHF 10,000 from the 2031 tax period? To what extent does Nik’s insolvency play a role?
- To whom are the following attributable in 2032: the wages, the income from the (50% transferred) investment account, the balance in the joint account, and the painting?
- Who will be held liable for the failure to report the investment account and its income on the tax return? Is there a difference from current law?
- Will Martina be granted access to Nik’s 2032 tax return? Does she have access to the joint tax records for the 2031 tax period?
](<#footnote-ref-2>)See the example and discussion by Hunziker/Mayer-Knobel, in: Zweifel/Beusch (eds.), Commentary on Swiss Tax Law, Federal Act on Direct Federal Tax, 4th ed., Basel 2022, Art. 13 N 6.
The Federal Direct Tax Act (DBG) of 2005 did not yet provide for the married-couple deduction (social deduction). It was not introduced until January 1, 2008 (Art. 35, para. 1, lit. c). For the purposes of this exercise, however, it is included in the case solution.
