Questione giuridica chiave
Whether the appeal should succeed on the alleged violation of the right to be heard.
Decisione estratta
The complaint failed because the cantonal court could, without arbitrariness, refuse the requested evidence as irrelevant or unnecessary.
Motivazione estratta
Anticipatory assessment of evidence is allowed under Art. 29 para. 2 Cst.; the appellants did not show arbitrariness in the refusal of file production, site inspection, witness, or expert evidence.