Article 26 establishes criminal sanctions for serious tax violations, including imprisonment for up to one year and/or fines up to three times the due tax. These penalties apply to taxpayers who submit forged documents, use fraudulent methods to obtain exemptions or refunds, deliberately fail to register, hide income, or obstruct Authority employees. These measures target intentional tax evasion and fraud, categorizing them as criminal offenses beyond mere administrative failures. By imposing both custodial sentences and heavy financial multipliers, the Law aims to deter high-level non-compliance and protect the integrity of the state's revenue system.