[7] In June 2005, Liu began serving as one of four caucus whips for the Taiwan Solidarity Union, alongside Ho Min-hao, David Huang and Kuo Lin-yung.

[9] Liu attended a fundraising event in January 2007, during which the Taiwan Association of University Professors announced that it was founding an online college.

[12][13] Questions regarding dual citizenship were also asked of Liu's former legislative colleague Diane Lee, who eventually resigned her seat.

[22] As Liu was stepping down, the Ministry of Foreign Affairs determined that he had displayed a lack of political judgment in delaying a letter from Switzerland's Federal Department of Justice and Police in regard to inquires about money laundering by the Chen Shui-bian family.

[25][26] The Central Executive Committee of the Taiwan Solidarity Union reached a decision to expel Liu from the party on 13 October 2008.