Key legal question
Whether the German request concerned tax fraud rather than a purely fiscal offence, allowing mutual legal assistance.
Extracted holding
The conduct described in Sachverhaltskomplex I could be treated under Swiss law as tax fraud through fraudulent concealment and fabricated rental arrangements, so assistance was permissible.
Extracted reasoning
The alleged creation of fictitious leases, a false guest register, and other deceptive steps formed a plan to mislead tax authorities about the suspect's residence. Such machinations were sufficiently deceptive and potentially caused underassessment of income tax.