Kernrechtsfrage
Whether the Solothurn tax authority may review an out-of-canton approved expense regulation and cap lump-sum expenses at 5% of gross salary.
Extrahierter Entscheid
Yes. Such regulations may be reviewed when the approved lump-sum expenses exceed the SSK-accepted 5% ceiling; the excess may be taxed as salary unless higher deductible expenses are proven.
Extrahierte Begründung
Inter-cantonal recognition of approved expense regulations is only a rule of administrative simplification. If the lump-sum allowance exceeds the generally accepted 5% of gross salary, the receiving canton may correct it within its tax autonomy.