[17] In June, Tuan stated that he would retire from politics at the end of his term in 2020, as he expected reforms he supported over the course of his legislature tenure to have been implemented by that time.

[19] Tuan claimed in January 2015 that President Ma Ying-jeou illegally accepted NT$200 million from various businesspeople during his 2008 presidential campaign.

[24] In December 2015, Tuan accused Wang Ju-hsuan of improperly profiting in the real estate market by acquiring multiple properties intended to house military families.

[26] Fellow Democratic Progressive Party member and incumbent Hualien City mayor Tien Chih-hsuan [zh] died in May 2016,[27] and the DPP lost the subsequent by-election in August.

[29][30] In September, Tuan accused Radio Taiwan International of "assisting" unification efforts, by renting low-cost airtime to the China-based Guangdong Television.