Electoral Boundaries: An Explainer

This post is part of CAPE’s GE2025 Voter Education Portal

CAPE EBRC infog 2025Download

The Electoral Boundaries Review Committee: More Than Just Lines on a Map

In Singapore’s political landscape, few processes are as influential yet as little understood as the work of the Electoral Boundaries Review Committee (EBRC). This group, appointed by the Prime Minister, reviews electoral boundaries before each general election, significantly impacting the country’s electoral map.

1. What is the EBRC?

The EBRC, typically composed of senior civil servants, recommends:

  1. The number of electoral divisions
  2. The boundaries of each division
  3. The number of Group Representation Constituencies (GRCs) and Single Member Constituencies (SMCs)

While seemingly administrative, these decisions can significantly influence election outcomes.

2. How Does the EBRC Work?

First, the Prime Minister appoints the EBRC and sets out the terms of reference for the committee. Past terms of reference included instructions to (i) consider population changes and new housing developments, (ii) change the average size of GRCs, and (iii) change the number of SMCs. 

During this process, the Prime Minister must act according to the Parliamentary Elections Act: they may specify the number, names, and boundaries of electoral divisions in Singapore, and must ensure that there are at least 8 divisions that are not GRCs at all times.

Next, the EBRC deliberates boundary changes in private to reflect changes in population size and new housing developments.

Thereafter, the EBRC submits a report to the Prime Minister, recommending the number of electoral divisions, the boundaries of each division, and the number of GRCs and SMCs. Finally, the Prime Minister presents the report to Parliament and the new electoral boundaries take effect in the upcoming elections. 

3. Why Does the EBRC Matter?

The EBRC’s recommendations affect:

  1. Representation: By determining the size and composition of constituencies, the EBRC influences how different communities are represented in Parliament.
  2. Electoral Dynamics: Changes in boundaries can affect the electoral chances of both ruling and opposition parties. For example, dissolving a constituency where an opposition party has been gaining ground can potentially impact that party’s electoral prospects.
  3. GRC System: The committee’s decisions on the number and size of GRCs directly impact how the GRC system functions, such as minority representation.
  4. Voter Engagement: Frequent boundary changes can make it challenging for voters to build long-term relationships with their representatives and for opposition parties to build support bases.

While the EBRC’s work might seem technical, understanding its role is crucial for citizens to comprehend the factors shaping their vote and representation.

4. From Westminster to Uniquely Singapore: The Evolution of Boundary-Drawing

Singapore’s approach to electoral boundaries has evolved significantly since independence, transitioning from a British colonial model to a system tailored to the nation’s needs.

Colonial Roots: The Westminster Legacy

When Singapore gained self-rule in 1959, it inherited the British Westminster system, including its approach to electoral boundaries. Members were elected through universal and compulsory voting in SMCs. The Rendel Constitutional Commission of 1954 laid out specific principles for delimiting electoral districts in Singapore, emphasising equal representation and the need to consider factors like geography and population density.

Early Independence: Adapting to a New Nation

After full independence in 1965, Singapore began to modify its electoral system:

  1. 1966-1987: Singapore maintained the SMC system, with boundaries regularly redrawn to reflect population changes.
  2. All-Party Boundaries Committee: In 1958, an all-party committee was formed to prepare electoral divisions for the 1959 General Election. This committee proposed creating a “permanent machinery for the delimitation of boundaries” after the election, though this recommendation was not implemented.
  3. Increasing Frequency of Reviews: Boundary reviews became more regular, occurring every 3-4 years to keep pace with rapid urbanisation and population shifts.

The 1980s: A Turning Point

The 1980s marked a significant shift in Singapore’s approach to electoral boundaries:

  1. Introduction of GRCs: In 1988, the PAP government introduced the Group Representation Constituency (GRC) scheme to ensure minority representation in Parliament. By requiring each constituency to have a team of multiracial candidates, where at least one candidate belongs to a minority racial community, the scheme sought to limit polarising ethnic voting. This fundamentally changed how boundaries were drawn and how elections were contested.
  2. Ethnic Housing Quotas: In 1989, the government introduced the Ethnic Integration Policy (EIP) to promote racial integration and prevent ethnic enclaves in public housing. By setting ethnic quotas in housing blocks and neighbourhoods, ethnic groups were dispersed across housing estates, which effectively reshaped the demographic landscape of electoral districts. This made it challenging for ethnically-based political parties to concentrate support in specific areas.
  3. Expanding GRCs: Over time, the size of GRCs increased, with some growing to include up to six members by the late 1990s.

Modern Era: Refining the System

Since the 1990s, Singapore has continued to refine its unique electoral system, with trends towards reducing GRC sizes, increasing SMCs, and facing increased public scrutiny of the boundary-drawing process. For the 2025 General Election, there is a peak of 15 SMCs since 1997 and GRC sizes are no larger than 5 members.

This evolution reflects Singapore’s pragmatic approach to governance, but has also led to challenges regarding the independence and transparency of the process.

5. Questions of Independence: How Singapore’s Electoral System Compares

How does Singapore’s EBRC system compare to those of other democracies with similar historical roots or domestic concerns? This section compares Singapore’s approach to electoral boundary management to the modern Westminster system, New Zealand’s mixed-member proportional system, and Malaysia’s approach.

The Modern Westminster System

The Westminster System, which Singapore inherited and adapted, originated from the UK. It features:

  • Independent Commissions: Unlike Singapore the UK uses four independent Boundary Commissions, one for each part of the country.
  • Regular Reviews: Boundary reviews typically occur every 8 years, or when Parliament passes a new law changing the rules.
  • Public Consultation: In contrast to Singapore, the process includes multiple stages of public consultation. Initial proposals are published, followed by a period for written comments. Public hearings are then held in each region. After considering all feedback, the Commissions publish their final recommendations, which are then implemented by Parliament.
  • Fixed Rules: The current rules fix the number of constituencies at 650, with seats allocated proportionally based on the registered Parliamentary electorate.
  • Quota System: Constituencies must have an electorate within 5% of the ‘electoral quota’, with a few exempt island seats.

New Zealand’s Mixed-Member Proportional System

New Zealand’s system, adopted in 1993, offers a different approach:

  • Mixed-Member Proportional (MMP) System: Introduced in 1993, this system aims to make Parliament’s composition, among other things, more reflective of the overall party vote. This is unlike Singapore’s plurality party bloc voting system.
  • Dual Ballot System: Voters cast two ballots – one for a district representative and one for a party list.
  • Maori Representation: Separate Maori electorates overlay the General electorates, with the number determined by Maori enrollment. This is similar to the GRC system in Singapore to ensure minority representation.
  • Independent Commission: Unlike Singapore, the Representation Commission, including political appointees and an independent chair, oversees redistribution.
  • Regular Reviews: Redistributions occur every five years after the census.
  • Public Input: In contrast to Singapore, the commission invites public submissions and holds hearings before finalising boundaries.

Malaysia’s Approach

Malaysia, sharing historical ties with Singapore, presents a system with both similarities and differences:

  • Constitutional Basis: The Election Commission is established by the Constitution but is not fully autonomous.
  • Commission Structure: The Commission has five members appointed by the Yang di-Pertuan Agong (King of Malaysia) in consultation with the Conference of Rulers.
  • Prime Minister’s Role: Like in Singapore, boundary change recommendations must go through the Prime Minister, who can make alterations before presenting to Parliament.
  • Rural Weightage: Allows over-representation of rural constituencies, a practice rooted in 1950s negotiations that aimed to balance representation but effectively ensures Malay political dominance. Initially limited to a 15% size discrepancy between districts, subsequent amendments removed this restriction. 

Singapore’s Unique Position

Unlike the UK and New Zealand, Singapore does not have an independent electoral commission. Instead, the EBRC sits under the Prime Minister’s Office, the Prime Minister appoints the EBRC without the need for Parliamentary approval, and the EBRC acts according to the Prime Minister’s terms of reference. Compared to the UK, New Zealand, and Malaysia, the public is also not privy to the EBRC’s deliberations–only the final recommendations are made public.

While some might contend that Singapore’s approach prioritises swift decision-making based on population changes and housing developments, others have raised questions on independence, rule of law, and transparency. Political scientists Netina Tan and Bernard Grofman noted that “[without] an independent Election Commission, opposition check in the Parliament or appeal process, the unilateral boundary changes can have partisan effects.” This leaves room for electoral manipulation, and might raise suspicions that elections are free but not fair. 

Legal scholar Kevin YL Tan also highlighted that the Parliamentary Elections Act (PEA) grants the Prime Minister with broad powers that might violate fundamental principles of the rule of law. He notes that “beyond [the] general edicts [of the PEA], there is absolutely no guideline on how the Minister’s power under Sections 8 and 8A will be exercised. There are, for example, no limits on the number of GRCs the Minister may create, or the composition of each GRC, save that each GRC should have at least one […] ethnic minority member.” Moreover, “there are no indications on how the Minister might decide how the “names and boundaries of the electoral divisions of Singapore” are to be determined and drawn up.” Without clear guidelines on the Minister’s exercise of power under Section 8 and 8A, the Minister is left to exercise discretion. As Tan notes, “the notion of an unfettered discretion is anathema to the concept of the rule of law, which requires that all persons, including the state are under the law, and that the law applies equally to everyone.” 

Finally, the lack of transparency in the boundary drawing process has been a point of contention. Then Non-Constituency Member Sylvia Lim surmised this challenge in parliament in 2010: “The entire electoral boundary re-drawing process is completely shrouded in secrecy, chaired by the Secretary to the Cabinet. There are no public hearings, no minutes of meeting published. The revised boundaries are released weeks or even days before Nomination Day. The report makes no attempt to explain why certain single seats are retained while others are dissolved, nor why new GRCs are created or old ones reshaped. Voters have changed constituencies at successive elections without moving a single step.”

These debates introduce the potential risks and perceptions associated with the current EBRC design. In the next section, we will dive into more specific concerns regarding gerrymandering and malapportionment.

6. The Risk of Being Seen as Gerrymandering

Without an independent elections committee, some political observers caution that EBRC’s decisions could risk being seen as gerrymandering–the manipulation of electoral boundaries to favour one political party or person. If a party can control the electoral boundary drawing process, they can dissolve certain districts while redrawing other districts to change district magnitude and improve their chances of winning. According to Tan and Grofman, this redrawing can involve “shoring up weak districts or paring down PAP strength in safe districts”, “ceding certain districts to the opposition in a way that wastes opposition votes”, “fragmenting the opposition strength and submerging its strength within a stronger pro-PAP larger constituency” or “drawing SMCs into which it can pack the opposition.”  

Under a plurality party bloc voting system like Singapore, increasing district magnitude makes it easier for the party that captures most votes in that district to capture all seats in parliament. Tan and Grofman found that “the rise in mean district magnitude is paralleled by a rise in aggregate level swing ratio over the same period.”  In simpler terms, this means that as constituencies get larger, the winning party is more likely to win a higher proportion of seats relative to their vote share.

7. Is this gerrymandering?

The redrawing of electoral boundaries can sometimes be perceived as attempts to gain political advantage. Let’s look at some specific examples that have raised questions:

Elimination of Braddell Heights SMC in GE 1997

In 1991, opposition candidate Sin Kek Tong of SMC Bradell Heights obtained close to 48% of the vote. However, in GE 1997, Bradell Heights was incorporated into Marine Parade GRC.

Elimination of Joo Chiat SMC in GE 2015

In the lead-up to the 2015 General Election, the EBRC removed Joo Chiat SMC. Previously in GE 2011, the seat was hotly contested between PAP candidate Charles Chong and WP candidate Yee Jen Jong who lost with a narrow margin of 2.04%.

Elimination of Sengkang West, Punggol East and Fengshan SMCs in GE 2020

Before the 2020 General Election, the EBRC removed three SMCs–Sengkang West, Punggol East and Fengshan–and formed a new GRC in Sengkang, consisting of the old Punggol East and Sengkang West, and some parts of the old Ang Mo Kio GRC. Notably, the eliminated constituencies were also the ones that faced strong competition between PAP and WP in GE 2015. WP had contested in all three single-member constituencies and had lost by less than 10% of votes in Fengshan and Punggol East SMCs.

These changes have raised questions about potential gerrymandering over the years, though the EBRC and government maintained that these shifts were necessary to reflect population changes, and that the electoral boundary drawing process is fair. For instance, in 2023, Leader of the Opposition Pritam Singh raised concerns about PAP’s political advantage from boundary changes, citing highly contested SMCs that were ultimately dissolved in the following elections. Senior Minister Teo Chee Hean denied gerrymandering accusations, noting that opposition-won constituencies remain unchanged.

Likewise, in 2024, concerns about gerrymandering were raised in parliament again. Progress Singapore Party (PSP) Non-Constituency Member of Parliament Hazel Poa observed the changes in number of SMCs from GE 1988 to GE 2015 that might raise suspicions of gerrymandering: “[Amongst] the SMCs where opposition scored below 40% of the votes, on average 58% were retained as SMCs. In comparison, where opposition scored between 40% and 50% of the votes, only 33% were retained on average. […] Without clear justification, it is difficult to tell whether the EBRC has changed the boundaries simply because of population shifts and housing developments or for other reasons. Suspicions of gerrymandering naturally surface and erode public trust.”

However, Minister-in-charge of the Public Service Chan Chun Sing maintained that the EBRC is independent and objective: “First, the EBRC does not have access to voting information and hence, does not make its recommendations based on voting patterns. The EBRC does not consult the PAP or any other political party. Party politics do not come into this exercise. The EBRC comprises senior civil servants with no party allegiance. Therefore, unlike other countries where political parties are involved in the boundary-drawing process, the EBRC’s compositions and processes are insulated from party politics.”

These contrasting viewpoints highlight the ongoing debate about the fairness of boundary changes in Singapore’s electoral system. While opposition parties argue that we should reduce the potential for gerrymandering in the electoral boundary drawing process, the government maintains that the process is fair and necessary to reflect population changes.

Regardless of the intent behind electoral boundary changes, the absence of independent oversight could undermine public trust. According to the Institute of Policy Studies (IPS) Exchange Series World Values Survey 2021, 95% of respondents indicated that honest elections were important to them. Given the importance of fair elections to Singaporeans, minimising the risk of perceived gerrymandering in the electoral boundary drawing process could help maintain public trust in the electoral system.

Given that the EBRC operates under the PMO, maintaining public trust in the electoral boundary drawing process could also help preserve the perceived credibility of the ruling party. Based on the IPS Post-Election Survey on GE 2020, while the PAP remains the most credible party in the eyes of the people, the perceived credibility of the PAP fell across all demographic groups from GE 2015. Demonstrating the fairness of the electoral boundary drawing process could thus preserve or improve the perceived credibility of the ruling party. 

8. Difference Constituency Sizes: Why is Your Vote More Powerful than Mine? 

When redrawing electoral boundaries, EBRC uses a 30% deviation rule to determine the minimum and maximum number of voters in an electoral division. For instance, assuming that the ratio of one MP serving 26,000 voters is maintained, the number of voters in a new electoral division must range between 18,200 and 33,800 (30% more/less than 26,000). By extension, a five-member GRC can have between 91,000 and 169,000 voters. The difference between the maximum and minimum of voters in this case is a whopping 86%.

To put this into perspective: How fair would a football match be if one team had 11 players and the other had 20? This 30% deviation in constituency sizes creates a similar imbalance in the power of individual votes.

While there is no standardised deviation used in democracies worldwide, political observers have argued that a 30% deviation is far too wide as it leads to an uneven distribution of voters, which implicates voter equality. With a 30% deviation, the ratio of the smallest to the largest constituency would be 1:1.86. This means that a voter in a smaller constituency has more voting power than another voter in a larger constituency since it takes fewer votes to send a representative to parliament. For example, in GE 2006, Potong Pasir SMC had just 15,888 voters, while Bukit Panjang SMC had 30,452 voters. In other words, it took twice as many voters in Bukit Panjang to send an MP to Parliament than voters in Potong Pasir. 

This raises an important question: Should your postal code determine how much your vote counts?

9. Malapportionment in Singapore: Myth or Reality?

Although the 30% deviation rule could be seen as an act of malapportionment for partisan gains, some scholars note that there is no clear evidence to support this claim. Tan and Grofman found that while constituency sizes vary, there is no consistent pattern favouring the ruling party: 

“If malapportionment is used for partisan gains then, we should expect to see a pattern in which the PAP strongholds are underpopulated and pro opposition strongholds are overpopulated. However, our study of the population sizes of pro-PAP and pro-opposition constituencies shows mixed results. [There is] little evidence of an overall pattern. In the four earliest elections, there were some differences in the pro-opposition and PAP strongholds in a direction consistent with the hypothesis of malapportionment being used for partisan ends. In fact, in 2006, 2011 and 2015 elections, the population discrepancies [were] in favour of the opposition, i.e. opposition strongholds were underpopulated.”

However, even if malapportionment is not used for partisan gains, Tan cautions that the uneven distribution of voters might still run into legal challenges: 

“If not all voters are treated alike, this may violate Article 12 of the Constitution which guarantees to all persons, “equal protection of the law”. Furthermore, the exercise of discretion with regard to constituency sizes and demographics bears no relation to the object of Section 8 of the PEA, which is to provide for free and fair elections on the basis of voter equality. This may therefore lead to a potential legal challenge on grounds of administrative illegality or irrationality.”

In short, while there’s no clear evidence of intentional malapportionment for partisan advantage in Singapore, the wide variation in constituency sizes raises important questions about voter equality and the fairness of the electoral system.

10. Recommendations Debated in Parliament 

Recently, PSP Secretary-General Hazel Poa proposed several revisions to the EBRC to address the issues we explored earlier:

(*This list is not exhaustive)

Establishing an independent EBRC 

The PSP proposed that the High Court judge chairs the EBRC, instead of the Secretary to the Prime Minister. The other four members of the EBRC–the CEOs of the Elections Department, HDB and SLA, and the Chief Statistician–may remain due to their rich domain expertise. 

However, Minister Chan pointed out that having a High Court judge chair the EBRC would not remove suspicions about the independence of the EBRC: “Other jurisdictions that have done so continue to face allegations and doubts concerning the independence of the electoral boundary delineation process. Their debate instead sinks into questions on who appoints the judge, and whether the judge has any political leaning or bias. The judiciary ends up getting drawn into the political debate, and the judiciary is politicised.”

The debate highlights key concerns over the separation of power between three branches of government: the Executive (which comprises the President and Parliament), the Legislature (which is led by the Prime Minister and  comprises the Cabinet ministers and office-holders), and the Judiciary.

Each branch serves a different function: the Legislature makes the law of the land, the Executive administers the law, and the Judiciary interprets the law through the Courts, ensuring that the Executive and Legislature comply with the rule of law. 

Although the PSP proposes having the EBRC chaired by a High Court Judge, to minimise the risk of unfettered discretion in decision making and maintain the separation of powers, the government cautions that this same movie might politicise the judiciary rather than protect the separation of powers. 

The debate reflects the different perspectives on maintaining the separation of powers, and ensuring that the judiciary is not politicised. 

Who do you think is a suitable candidate to chair the EBRC? 

Reducing the margin of deviation

The PSP also proposed revising the margin of deviation to 10%, citing examples of the UK and Australia, to ensure fair distribution of duties among MPs, and fairer voting weightage. “PSP proposes that one MP should represent 30,000 voters, with a deviation of plus or minus 10 per cent, such that each MP represents 27,000 to 33,000 voters. This would bring about a fairer distribution of duties amongst MPs, and is fairer to voters in terms of their voting weightage.”

However, Minister Chan explained that due to Singapore’s smaller population and higher population mobility, a narrower margin of deviation could lead to several unintended consequences:

  1. More frequent boundary changes: With a smaller population base, even minor population shifts could trigger boundary adjustments if the margin is too narrow.
  2. More disruptive redrawing: Smaller constituencies are more sensitive to population changes, potentially requiring more extensive redrawing to meet a tighter deviation standard.
  3. Potential loss of community continuity: Frequent changes could disrupt the formation and maintenance of community ties within constituencies.
  4. Impact on MP-constituent relationships: Constant redrawing could affect the ability of MPs to serve their constituencies effectively over time.

That said, it appears that some of these issues are already a result of the current electoral boundary design. Dissolving SMCs to form GRCs, renaming electoral divisions, and changing the composition of constituencies within each division influence MPs’ ability to serve their residents, and the formation and maintenance of community ties within each constituency over time. How then can we ensure fairer voter weightage and distribution of MP duties without exacerbating the issues associated with boundary changes? 

Conclusion 

In conclusion, the EBRC’s work goes beyond mere administrative adjustments; it fundamentally affects electoral dynamics and outcomes. While electoral boundary shifts are critical to reflect demographic changes and new housing development, the design of the EBRC and the boundary-drawing process has invited scrutiny. Debates surrounding the EBRC’s independence and its relatively opaque decision-making process have raised concerns about the rule of law, gerrymandering, and malapportionment. These debates highlight a crucial tension between efficient electoral boundary management, democratic fairness, and public trust. They also provide valuable insight into the priorities and trade-offs of different electoral boundary management systems. 

Food for Thought

  • Does the current electoral system prioritise efficiency over independence?
  • What are the trade-offs involved in different approaches to managing electoral boundaries?
  • How can we balance the need for electoral boundaries to reflect population changes and ensure minority representation, as well as the desire for constituency stability?
  • Who or what institutions would be suitable candidates to chair the EBRC? 

References

Related Posts

Scroll to Top