1981 Anson by-election

The by-election was held in Singapore on 31 October 1981. The by-election was to replace the vacant seat after the incumbent MP, Devan Nair, stood down in order to become President of Singapore.

The result was a victory for J. B. Jeyaretnam from the Workers' Party winning 51.93% of the vote and he was declared as Member of Parliament for Anson Constituency.

The by-election marked the first occasion since Singapore's independence in which a PAP candidate was defeated in an election for a seat in Parliament. The 37% swing against the PAP is the largest ever swing in a by-election in independent Singapore, and the second largest since 1961.

Candidates
The Nomination Day for the by-election was 21 October 1981. The election deposit for candidates was set at $1500. Three candidates stood in the by-election: Pang Kim Hin (the nephew of former minister Lim Kim San) of the PAP, J.B. Jeyaretnam of the Worker's Party and Harbans Singh of the United People's Front (UPF). The leader of the Singapore Democratic Party (SDP), Chiam See Tong, also considered standing in the by-election, but decided to withdraw at the last minute and leave Jeyaretnam to be the PAP's main opponent in the name of "opposition unity".

Result
Note: As Habans Singh of United People's Front failed to garner the minimum 12.5% (one-eighth) of the votes necessary to keep his deposit, his election deposit was forfeited.

Aftermath
This is one of the most significant elections in Singapore's political history because it was the first opposition victory since the Barisan Sosialis had left Parliament in 1966. It was the third by-election to have been held in Anson.

The election marked the Workers' Party's return to Parliament after 18 years. The last time they won an election was back in 1961, when David Marshall also won a by-election in Anson as a candidate for the party (however he lost the seat in the 1963 general election).

A number of factors are thought to have contributed to PAP's defeat in this by-election. One of them was Pang was a new face to the public in Singapore whereas Jeyaretnam was a veteran of several general elections and by-elections (though this was the first time he had stood in Anson). Another factor may have been that Pang did not make use of Anson's grassroots leaders during his campaign. Another issue surrounding the campaign was that residents in the Blair Plain area of the constituency were unhappy that they were not being given priority for HDB flats when their homes were being demolished to make way for a new Port of Singapore Authority container complex, and some voters may have used the by-election as an opportunity to express discontent regarding this.

Following the by-election, Pang announced his retirement of politics, though he was offered a place in the next election, he ultimately declined, making him the first PAP candidate to never enter parliament. He remained the only candidate to do so until Eric Low in the 2001 election before retiring in 2011.

Jeyaretnam successfully retained the seat with a larger majority of 2,376 votes in the 1984 general election, when he defeated the PAP's Ng Pock Too. He captured 56.8% of the votes in the constituency in that election.

Harbans Singh became the first candidate in Singapore election history to have forfeited his election deposit twice, with the first occurring on the 1976 elections contesting under Tanjong Pagar with 11.0% of the valid votes.

Although the PAP has remained the dominant party in Singapore politics due to a supermajority, it has never again held a complete monopoly of all the seats in Parliament since the 1981 by-election.