Article 19, Paragraph 3, of the Tax Levy Act stipulates that for all kinds of notifications issued for the purpose of tax collection, “the legal effect of the service of process to any individual joint owner will be applied to all joint owners as though all have been timely served.”　When applied to the administrative act of tax assessment, the quoted stipulation will produce the legal effect that a service of process to any individual joint owner will be deemed as services of process to all joint owners.　It is inconsistent with the constitutional mandate of due process of law and infringes the constitutional rights of the joint owners who are never actually served both to institute administrative appeals and to institute legal proceedings, and is hence in contravention of Article 16 of the Constitution.　Therefore, the quoted stipulation shall be inapplicable no later than two years after we hand down this interpretation.

　　People’s property rights, right to institute administrative appeals, and right to institute legal proceedings are constitutional guarantees under Articles 15 and 16 of the Constitution.　The service of process of the notification of tax assessment not only involves the limitation of people’s property right, but also closely relates to the fact whether people can be aware of the content of the notification and to people’s ability to institute administrative proceedings to redress their grievance.　Article 16 of the Constitution guarantees that when people’s rights are infringed by the administrative acts, the grieving one will have the right to institute administrative appeals or administrative proceedings under the administrative procedure stipulated by the government to seek for appropriate remedies.　The implementation of this constitutional guarantee and the scope of this procedural fundamental right to institute legal proceedings are reserved to the legislative branch to enact relevant procedural laws pursuant to the due process of law.　In order to determine whether the relevant procedural laws enacted by the legislative branch are the products of the due process of law, in addition to take into account the constitutional guarantees and fundamental rights involved, we will take into account following factors, both respectively and as a whole, which are the subject matters involved, the scope and degree of the infringement of fundamental rights, the public interests sought, the availability of alternative procedures and the cost of alternatives. (See J.Y. Interpretations No. 459, 610 and 639.)

　　Article 19, Paragraph 3, of the Tax Levy Act stipulates that for all kinds of notifications issued for the purpose of tax collection, “the legal effect of the service of process to any individual joint owner will be applied to all joint owners as though all have been timely served.” (hereinafter the “stipulation at issue”)　Pursuant to the “stipulation at issue”, the pertinent tax authority may fulfill the legal requirement of a due service of process by having the notification of tax assessment to joint owners delivered to any given individual joint owner and hence produces the legal effect of the service of process to all joint owners regardless whether in the first place the pertinent tax authority fulfills its duty to check if there are joint owners and to serve those joint owners whose addresses are unknown by posting or publishing the notification.　The legislative history of the “stipulation at issue” shows that the legislative intent is to try to accommodate the practical difficulty of serving individual joint owners of large and disbursed properties such as ancestral estates in joint ownership whose owners are often large in number and have scattered residences.　It is especially true to those ancestral estates in joint ownership that have no designated managers. (See the Legislative Yuan Gazette, Volume 65, Issue 79, Page 48-49.)　It is clear that the “stipulation at issue” was enacted with a view to enhance public interests such as to reduce the cost of tax collection and to promote administrative efficiency.

　　However, under the due process requirement of administrative procedure in a rule of law state, the pertinent tax authority shall voluntarily investigate relevant evidence to find out the facts in any given case and to discover the right one who is subject to a specific administrative act. (See Article 36 of the Administrative Procedure Act.)　Further, the pertinent tax authority shall employ a due service of process or other appropriate means to enable the one who is subject to an administrative act to be aware of or to have the opportunity to be aware of the specific administrative act, and therefore to enable she to institute administrative proceedings accordingly.　Furthermore, Article 35, Paragraph 1, of the Tax Levy Act prescribes that any taxpayer who disagrees with the administrative act of tax assessment shall file a petition of review within thirty days after the second day of the end of the expiration period when the notification of tax assessment comes with a specified amount of tax payable or of additional tax payable; the disagreeing taxpayer shall file a petition of review within thirty days after the service of process when the notification of tax assessment comes with no specified amount of tax payable or of additional tax payable.　Accordingly, pursuant to the “stipulation at issue”, since the legal effect of a service of process to any given individual joint owner applies to all joint owners, the statutory period for filing a petition of review to all joint owners shall begin to toll when there is a service of process to any individual joint owner.　However, since the service of process is delivered to an individual joint owner only, and since the joint owner served may not inform other joint owners, the other joint owners may not be aware of the notification of tax assessment and will not be able to file a petition of review timely.　Besides, the statutory period for filing a petition of review is as a matter of law a statutory peremptory period and no taxpayer may file such a petition when the period ends.　Thus, the “stipulation at issue” severely infringes the rights of joint owners who are not served to institute administrative appeals and to institute legal proceedings.

　　Even if it is the case that there are joint owners who shall be served yet whose residences are unknown, the pertinent tax authority may still be able to post or to publish the notification of tax assessment, or to employ other means that will not generate excessive administrative cost and will have the content of the notification easily known to other joint owners in order to accomplish the statutory purpose of requiring a due service of process.　Therefore, the “stipulation at issue” deprives of other joint owners’ right to be duly served and imposed limitation on people’s right to institute administrative appeals and right to institute legal proceedings way beyond the degree of necessity.

　　To sum up, to the extent of the above mentioned rationales, the “stipulation at issue” is a procedural law which is both unreasonable and unjust, and is inconsistent with the constitutional mandate of due process of law, and is in contravention of the constitutional guarantees of people’s right to institute administrative appeals and people’s right to institute legal proceedings under Article 16 of the Constitution.　To take into account that fact that when the pertinent tax authority has the notification of tax assessment delivered to every known joint owner, the calculation of tax overdue charges may be affected as the dates of the services of process may be different and the tolls and expiration dates of the statutory period of filing petitions of review may also be different, and to take into account that fact that after considerable investigations the pertinent tax authority may still be unable to or may confront apparent difficulty to locate every joint owner of ancestral estates in joint ownership or other joint-owned properties owing to inheritance because of the elapse of time, because of the large number of descendents, or because of the inheritors who are unknown, it will take up considerable time to design how to employ other appropriate means to serve every individual joint owners and at the same time to satisfy the premise of due process of law and to evaluate the factors such as people’s right to institute administrative proceedings, the cost of tax collection, and administrative efficiency.　The “stipulation at issue” shall be inapplicable no later than two years after we hand down this interpretation.