[15] After an October 2024 fire at the Antai Tian-sheng Memorial Hospital killed nine people,[16][17] Su was questioned by the Pingtung District Prosecutors' Office and released on bail in February 2025.

[18] Su contested the 2008 legislative election as a Kuomintang candidate from Pingtung County's third district, losing to Pan Men-an.

[25] In January 2015, an amendment to the Fisheries Act proposed by Su passed, waiving a requirement that Taiwanese maritime employers pay health insurance premiums for foreign employees dating back to 2009.

[26][27] In 2013, Su backed an amendment to an environmental impact assessment, permitting the proposed projects to continue in water catchment areas near reservoirs.

[36] Though it was reported in March 2015 that Su was considering running for reelection to the Legislative Yuan from his native Pingtung County,[37] by August, his willingness to contest a geographical constituency in Southern Taiwan had been reduced.

After the preliminary results were announced, Su claimed that there were several errors in the vote counting process and petitioned for a recount.

[42] Su returned to the Legislative Yuan in 2024, via the Kuomintang party list,[43] and again served as a convenor of the Social Welfare and Environmental Hygiene Committee.