Article 172 defines the trial procedures for tax suits. It prohibits third-party intervention and allows the Tax Authority to present new pleas or counterclaims to sustain its assessment during the session. Evidence is restricted to written documents, accounting records, expertise, and admissions; oral testimony (oaths/witnesses) is excluded to maintain the documentary nature of tax proceedings. Where this Law is silent, the Civil and Commercial Procedure Law and the Law of Evidence apply. These terms ensure that tax litigation remains a technical, record-based process focused on financial evidence rather than verbal testimony.