The by-election was to replace the vacant seat after the incumbent MP, Yaw Shin Leong was expelled from the Workers' Party and his extramarital affairs.

The announcement came after weeks of speculation and rumours that Yaw had an alleged extramarital affair with a fellow party member.

[8] Within 30 minutes of 20:37, news reports detailed the mixed reactions among Hougang residents to Yaw Shin Leong's expulsion,[9] Prime Minister Lee Hsien Loong's comment that there is no fixed time within which a by-election must be called,[10] and People's Action Party Chairman Khaw Boon Wan's quote that Hougang voters have been misled by the WP.

[12][13] In the days following the announcement, a war of words ensued between Aljunied GRC MP Low Thia Khiang, former MP Ho Kah Leong and government press secretary Foo Kok Jwee in the letters columns of the Lianhe Zaobao and The Straits Times over the degree to which the situation compared to the last by-election in 1992 and whether or not the expulsion of Yaw was an "abuse of the democratic system" to save the party's integrity.

Tan argued that although the Constitution did not impose a timeframe within which a by-election had to be held, it was not the intent that this should allow elections to be postponed indefinitely.

[8] Mr Tan argued that this state of affairs should not continue for the projected remaining term of the current Parliament of four and a half years.

[18] Two other potential candidates had originally also signalled their intent to run, having collected their political donation certificates, a prerequisite for contesting.

[20][21] At 10.30pm (SGT), results were announced by Returning Officer Yam Ah Mee at Holy Innocents' High School where WP's Png retained Hougang SMC with 62.08% of the valid votes, beating PAP's Choo with 37.92%.