To avoid permanent liabilities of taxpayers and to promote enforcement agencies' efficiency, for unpaid tax cases not settled before 5 March 2007 (the "Pending Cases"), the Legislative Yuan amended Article 23 of the Tax Collection Act in 2007 requiring enforcement agencies not to take any action for the Pending Cases beginning from 5 March 2012. But this has been seen by the public as an amnesty to dishonest taxpayers, which is obviously unfair to those honest taxpayers. Accordingly, the Ministry of Finance proposed to amend Article 23 of the Tax Collection Act to extend the enforcement period of the Pending Cases till March 4, 2017. However, considering the broad coverage of the amendment, the Legislative Yuan has limited the coverage of the amendment to Pending Cases that meet certain requirements (the "Serious Unpaid Tax Cases").

A Serious Unpaid Tax Case is a case that meets any one of the following requirements: (a) the total unpaid tax as of 4 March 2012 (including the tax payable, delinquent payment penalty, interest, delinquent filing penalty and fines for national taxes (excluding customs duties) and local taxes) is NT$500,000 (approximately US$17,000) or more; (b) enforcement agencies have obtained a detention or custody order from an administrative court before 4 March 2012; or (c) enforcement agencies have issued an injunction order to prohibit a taxpayer from living extravagantly before 4 March 2012.

The amendment passed by the Legislative Yuan, which has extended the enforcement period for Serious Unpaid Tax Cases, may be unconstitutional. However, before it is declared unconstitutional by the Grand Justices, those taxpayers in Serious Unpaid Tax Cases will still face enforcement risks.