A Literature Review on the Paradoxes of Public Interest in Spatial Planning within Urban Settings with Diverse Stakeholders

Abstract

The concept of public interest legitimises the planning profession, provides a foundational principle, and serves as an ethical norm for planners. However, critical discourses highlight the problems of the assumptions underlying the notion of public interest in spatial planning. Using an explorative literature review approach, the article aims to analyse various interpretations and applications of public interest in spatial planning. The literature search process, conducted between August and November 2023, targeted journal articles and books published in English and focused on the online databases of Academic Search Premier, Scopus, and Google Scholar. The final selected literature comprised 71 sources. The literature showed that diverse conceptualisations of public interest complicate the ways spatial planners and authorities incorporate it in planning tools, processes, and products. This article concludes by arguing that the prospects of achieving a single definition of the public interest concept are slim and may not be necessary given the heterogeneous conceptualisation and the multiple operational contexts of public interest. The article recommends the development of context-based analytical frameworks to establish linkages that would lead towards the equitable inclusion of public interest in spatial planning.

1. Introduction

Spatial planning, which coordinates the spatial dimensions and outcomes of various economic, social and environmental initiatives across different spatial scales [1], is central to moving society towards sustainable development [2]. According to Fischler [3], spatial planning is recognised as striving to achieve ‘public interest’. As recapitulated by Alexander [4], the ‘public interest’ concept legitimises the planning profession, provides a foundational principle, and serves as an ethical norm for planners. Despite the acclaimed interconnections, critical discourses point to the problems of the assumptions underlying the notion of public interest in spatial planning [5,6,7,8]. According to Dadashpoor and Sheydayi [9], one questionable assumption is that public interest aligns with enhancing the well-being of all stakeholders affected by planning projects. However, when dealing with complex development plans and projects entailing diverse interests and values, a pluralistic approach becomes necessary in delineating public interest [9]. Tait [8] sought a deeper understanding of the term ‘public’, calling for different interpretations in contexts extending beyond the community planning scale. This inquiry stemmed from the assertion that such contexts encompass broader geographical zones and inherently encompass multiple communities with divergent interests [10]. Consequently, it is not unusual to anticipate conflicts of interest in such settings [11].

The critics further contend that, due to its vagueness, the concept of public interest is difficult to operationalise [11]. Others even argue that public interest is rhetoric used to protect the interests of the elite [6,7,12], exacerbating societal inequalities and exploitation of low-income groups [13,14,15,16].

In light of these debates, this article aims to analyse various interpretations and applications of public interest in spatial planning found in the literature. The article’s point of reference is urban settings with diverse stakeholders with different and potentially conflictual interests.

The article is structured as follows: The second section describes the literature review methods utilised in the study. The third section presents the findings from the literature review, revolving around public interest’s depiction in spatial plans, planners’ understanding of public interest, consideration of community members’ views in defining public interest, and challenges of quantifying public interest. The fourth section synthesises the literature and discusses the meanings of ‘public’ and ‘interests’. The fifth section concludes the paper.

2. Methods

This study used an exploratory literature review approach to analyse the connections between public interest and spatial planning. The process began by identifying keywords for the literature search, namely ‘public interest’, ‘spatial planning’, ‘public participation’, and ‘land-use planning’. The literature search process, conducted between August and November 2023, focused on peer-reviewed journal articles and books written in English. Because of the study’s explorative nature and the reviews’ comprehensiveness, the search was not restricted to particular years of publication. Boolean logic operator ‘AND’ was used to combine the keywords in searching for books and journal articles on the Academic Search Premier, Scopus, and Google Scholar online databases (

Table 1. Search strings and the number of publications per database.

Database	Academic Search Premier	Scopus	Google Scholar
Search Strings	‘public interest’ AND ‘land-use planning’ n = 42	‘public interest’ AND ‘land-use planning’ n = 44	‘public interest’ ‘land-use planning’ n = 18
	‘public interest’ AND ‘spatial planning’ n = 44	‘public interest’ AND ‘spatial planning’ n = 37	‘public interest’ ‘spatial planning’ n = 12
	‘public participation’ AND ‘spatial planning’ n = 103	‘public participation’ AND ‘spatial planning’ n = 58	‘public participation’ ‘spatial planning’ n = 47
	‘public participation’ AND ‘land-use planning’ n = 80	‘public participation’ AND ‘land-use planning’ n = 59	‘public participation’ ‘land-use planning’ n = 19
Total	269	198	96

).

The abstracts and introductions of the identified literature were perused to assess if they discussed the interpretations and/or applications of public interest in spatial planning. The literature that did not was deemed irrelevant and excluded from the study. The reference lists from the first set of relevant literature were perused to identify related publications through backward snowballing [17], and the identified articles were screened by reading the abstracts and introductions so only the relevant literature remained. Citations from the shortlisted articles were then used to identify more publications using forward snowballing [17].

The final selected literature comprised 71 sources, including 63 journal articles and 8 book chapters. Figure 1 shows that the reviewed literature ranged from 1960 to 2023, with the majority published between 2010 and 2019, reflecting the currency of the topic. This literature was then used to analyse and synthesise [18] the various interpretations and applications of public interest in spatial planning.

The literature search process followed in the study is summarised in Figure 2. However, it should be noted that, as in part a limitation of the study, the process relied heavily on snowballing, which made it difficult to pinpoint with accuracy the number of relevant sources from each database; hence only the total number of studies found through the search strings is reflected in Figure 2.

3. Findings

The literature review findings presented in this section are organised around the interconnected elements of the public interest’s depiction in spatial plans, planners’ and authorities understanding of public interest, consideration of community members’ views in defining public interest, and challenges of quantifying public interest.

3.1. Public Interest’s Depiction in Spatial Plans

The depiction of public interest in spatial plans takes two main formats: policy statements and planning regulation or land use zoning [19]. The extent to which these are applied depends on the plan’s spatial coverage and policy level.

3.1.1. Policy Statements

The public interest depicted in policy and strategic statements is common to the high-level plans [7]. These plans usually view public interest based on principles, universal definitions, and ubiquitous values, described with general terms such as housing for all; protecting the natural environment; and equal access to public facilities, clean water, clean air, and public transport facilities [8,9,20]. However, these principles are criticised for being near-meaningless idioms that are not easily translatable into tangible entities [6,7,21]. Tait [8] further argued that there are pertinent questions about the scale of the public, where there are typically tensions between public interests defined at the local and national levels.

3.1.2. Land Use Zoning

At a local or neighbourhood scale, public interest can be portrayed in the form of land use zoning. Although the purpose of zoning is varied, this article highlights the following roles that directly impact the interests of individuals and communities: zoning alleviates market failure and other negative externalities, including the social cost of development and the failure to provide public goods and services; it protects property values and citizens from the adverse effects of new development [22]; and it encapsulates a broader comprehensive urban planning scheme that makes cities more orderly and better by placing every activity in its own space [22,23].

Spatial planning’s dependency on zoning for advancing the public interest is a subject of debates mainly premised on criticism that zoning interferes with individual liberties. However, arguments legitimising the planning profession are mainly based on the planners’ claim to being specialists in land use allocation and defenders of the public interest [24].

Zoning is often criticised for being too restrictive, lacking fairness, exclusionary, and inefficient [25,26,27]. The critics argue that the excessive use of regulatory control in urban areas can exacerbate urban sprawl, as it encourages residents to move to suburban areas in search of less-regulated space. Zoning is labelled unfair for practising favouritism that protects the rights of some landowners at the expense of others. Those claiming that zoning is inefficient base their argument on the unnecessary transaction costs incurred in executing zone-based development management [27].

Zoning is also blamed for facilitating oppressive policy objectives that promote racial, social, and economic segregation. Kamete [25] further interrogated the reasons behind the abuse of planning instruments such as zoning and development control. He contended that planning is used to settle political grudges through the systematic spatial displacement of dissenting communities. He cited the infamous Operation Murambatsvina/Restore Order (OM/RO) of 2005 in Zimbabwe, which he averred was targeted at eliminating political opponents of the ruling party. In the OM/RO, which was effected at the Harare city scale, order (represented by zoning) and the removal of filth were the only factors the authorities used to define public interest [25]. Informal settlements and non-formal livelihood sources inferably could not qualify under the public interest banner. Therefore, the public interest phenomenon was used to marginalise informal settlers and businesses [25] across the City of Harare.

Although most accusations regarding unfairness predominantly stem from the advocates of public rights, landowners also claim to be victims of discrimination that prioritises the public interests over legitimate property rights [28]. Codes [28] argued that zoning decisions being made on a highly localised scale tend to lead to more frequent conflicts compared to decision-making processes found in other scales.

Despite the criticisms, zoning remains a dominant mechanism for effectuating development management in the defence of public interest. Qian [22] referred to the case of the US city of Houston, which failed to achieve equity objectives because authorities allowed private actors to manage development. In Karkkainen’s [27] view, it is irrational to criticise zoning for prioritising private property rights over public rights. Instead, it should be seen as a means of safeguarding residents from potential ramifications of future developments, such as noise, air, and water pollution. The author commended zoning for safeguarding what he terms ‘consumer surplus’, which relates to the distinction between a house and a home, a concept also described by Cordes [28] (p. 639) as “preserving the sanctity of the home”. By defending the consumer surplus, the author referred to the role of zoning in maintaining continuity, familiarity, and the intimate connection between citizens and their habitats. Lastly, he mentioned that zoning is particularly effective when allocating and protecting what he called ‘neighbourhood commons’ and ‘neighbourhood quasi-commons’. The protection of neighbourhood commons means giving open access to communally owned spaces. Quasi-commons refer to privately owned facilities that provide necessary amenities to locals [27]. From an urban design point of view, defending neighbourhood commons not only enhances the sense of identity and place-making but also improves the ambience and aesthetics within the neighbourhoods [29,30]. For urban designers, shaping and maintaining beautiful urban landscapes engenders the hedonic value of a place [31]. This, in turn, can be construed as a boost to the overall quality of life, thereby enhancing public interest.

Cordes [28] defended zoning using a different argument that contends there is complementarity between private interests and the public interest at a localised scale, which yields benefits to all; hence both types of interests must be defended. The argument rekindles the view regarding public interest as equivalent to aggregated private interests. In this regard, private property is a necessity that enhances personal autonomy and privacy. Such conditions are needed to support individuals’ and communities’ well-being; therefore, it becomes a prerogative of the state to defend them (ostensibly using land use regulations tied to zoning). Cordes [28] also acknowledged the role of private interests in enhancing the public good by providing essential goods and services that benefit the public in general. For Cordes [28], the primary function of zoning is to protect private land by minimising conflicting uses at a localised scale, and it is not about depriving landowners of some development opportunities, as some critics would argue [28].

The physical nature of spatial planning entails defining the public interest by prescribing land use and allocating development rights to individuals or groups at a local scale. In most cases, one individual group’s interest prevails over another, rendering the process a source of class conflict and power contestations [8,10,25]. Arguments for and against the use of zoning have genuine concerns that impact not only the ethical perceptions of public interest but also the distributive aspects of spatial planning. The concerns also highlight how scholars and communities value diverse interests.

3.2. Planners’ and Authorities’ Understanding of Public Interest

Planners and authorities interpret public interest in varied ways. For instance, Howe’s study [32] on United States (US) planners’ views on public interest drew the following key findings, showing the contradiction that lies within planners’ views on the meaning and application of public interest: one, the planners agreed that their views alone could not adequately define public interest, acknowledging contributions from other actors; two, some planners believed that policy and zoning plans represented public interest; three, communities’ contributions towards defining the public interest were insignificant, because they did not have the knowledge levels of planners on socioeconomic and market issues and could not make meaningful contributions to planning processes. The subsections below discuss the conceptualisation of public interest and market rationality, which affect the planners’ understanding of public interest.

3.2.1. Planners’ Conceptualisation of Public Interest

Some of the confusion in the planners’ conceptualisation of public interest results from inconsistency in the philosophical orientation and frameworks that underpin spatial planning. The ‘deontological’ approach sees public interest as right or wrong (meaning that it is about the moral worth of the planning methods and affording equitable rights to the use of resources), while the ‘teleological’ approach sees public interest as good or bad, concerned with the long-term consequences of policies and programmes [32].

‘Teleological’ planning perspectives have had a significant and enduring influence on planning history and remain the foundation on which most contemporary planning practice is based [33]. Despite their continued prominence, these perspectives face many challenges in dealing with pluralistic societies, especially in the absence of commonly shared values. In response to these challenges, planning theorists (mainly from the communicative planning theoretical school of thought) adopted ‘deontological’ approaches they saw as more amenable to managing pluralist societies. However, the ‘deontological’ approach’s operationalisation conflicts with the technical procedures that underlie most planning tools, particularly land use management [33,34].

The relevance of the debates on philosophies to planning practice was discussed more nuancedly by Slaev et al. [35] through a comparative analysis of the application of ‘teleocratic’ and ‘nomocratic’ approaches to public interest. The ‘teleocratic’ approach is ideal for monocentric systems where all resources belong to one owner. In contrast, the ‘nomocratic’ approach is more suitable for managing scenarios with pluralistic interests. The main difference between the two is that ‘teleocracy’ depends more on the planner’s expertise to determine the public good whilst ‘nomocratic’ decisions depend on citizens’ views [35].

3.2.2. Market Rationality

Several respondents (planners and authorities) in the studies reviewed showed that some planners conflated the ‘market rationality’ concept with public interest [8,32,36]. For instance, in the United Kingdom, development that supported economic growth was synonymous with the public interest and the market as the arbiter of public interest, ignoring democratic participation at a local level [8]. In Serbia, most believed that, at citywide and neighbourhood scales, land-use planning was subordinate to economic interests [19].

The economic-led approach to spatial planning is also mired with negativities exemplified by frustrations expressed by Swedish planners over changes from a government-centric approach to a governance-oriented one [36] at municipal or local scales. While government denotes an entity with the power to manage a particular territory, governance emphasises a bottom-up process involving various stakeholders in managing the affairs of a territory [37]. At a local scale, the Swedish planners were concerned about disrespecting their professional integrity by being relegated from decision-making roles to being mediators. Norwegian planners raised similar concerns in an environment where the private sector had taken over the responsibility for preparing over 90% of the country’s zoning plans [38].

3.3. Consideration of Community Members’ Views in Defining Public Interest

The reviewed empirical studies hardly used the perceptions or views of ordinary individuals and community members as the basis for defining public interest. For instance, studies in Poland and Portugal [39], Norway [38], Finland [40,41], Sweden [36], Serbia [19], Ireland [6], South Africa [42], and the United States [32] relied on interviews with public officers, planners, and politicians.

Several of the reviewed studies discussing cases and approaches to spatial planning on the African continent implicitly discussed public interest through forced evictions of people to give way to projects that are deemed to represent better public interest [25,43,44,45]. For instance, across various states in Nigeria, authorities are blamed for using development control tools to prioritise the development of new infrastructure. Forced evictions on spaces occupied by low-income groups are carried out in the name of public interest to create space for infrastructure development [45]. Ocheje [43] also highlighted similar instances where forced evictions were implemented at different scales in the former English and French African colonies on the grounds of being in the public interest. Instead of public interest, Ocheje [43] presented three alternative explanations for the displacements: outdated planning laws, corruption, and economic development aspirations.

Justification for mega projects and new cities usually comes from the ‘right to develop’ mantra raised by the business and political elites [46]. However, the main contention against the new cities is that they displace the poor and vulnerable communities that do not have the political and financial muscle to contest eviction. Further depicting the incongruence between utopian planning visions and contextually constructed understanding of public interest, Myers [47] cited cases where ordinary people reframed urban spaces (informal change of use) in African cities.

To further dissect the consideration of community views in defining public interest, the intertwined subsections below present debates on the importance and efficacy of public participation in capturing and representing the public interest, technological tools to facilitate public participation, representative democracy, and public-centred democracy.

3.3.1. Public Participation as a Means to Capture and Represent Public Interest in Spatial Planning

Public participation at different scales is meant to capture public interest in spatial planning [48]. There are, however, debates questioning the authenticity, inclusiveness, and rationality of authorities and planners when they engage the public in scales ranging from individual buildings to nationwide surveys [49]. For instance, Hanssen’s study [19] of the Norwegian planning system found that most planners only involved the public in the planning process when it was legally mandatory. This reflects a gap in planning practice that justifies the need to investigate further the potential role and inclusion of the communities’ views on public interest in spatial planning. In Portugal, although the law requires that draft planning documents be subjected to thirty days of public debate, a municipality reserves the right to reject proposals they deem non-conforming with spatial plans [39]. Serbian planners described public participation and public interest as non-transparent, tokenistic tools for facilitating top-down decision-making, epitomising the negativities associated with the concept in planning practice [19].

The meaning and impact of public participation are subject to scrutiny following Arnstein [50], who proposed a typology of citizen participation in the form of a ladder applicable to scales ranging from local to national contexts. The analogy compared levels of participation with seven rungs of a ladder, where the most ineffective type of participation is represented by the bottommost rung and the highest level, ‘total citizen empowerment’ (also referred to as delegated power), is at the top of the ladder. Therefore, according to Arnstein [50], ‘total citizen empowerment’ should be considered the ideal public participation.

‘Total citizen empowerment’ was implicitly supported by Quick and Feldman [51], who highlighted the differences between ‘participation’ and ‘inclusion’. They contended that ‘inclusion’ is more appropriate in capturing public interest, because it involves individuals and communities in decision-making and the coproduction of plans. By contrast, according to Quick and Feldman [51], ‘participation’ at a local scale is a process that only registers public input into the contents of policies and plans. Krek [48] further demeaned the value of ‘participation’ by defining a participant as one who contributes something to a superior entity to contribute to some high-level goal. This view implies that public participation’s validity is conditionally dependent on the superiors’ powers. Some critics, therefore, label public participation a rubber-stamping exercise legitimising predetermined ideas [38,52].

There is a belief amongst some planners and authorities that public participation is retrogressive, time-consuming, costly, unwieldy, chaotic, and unproductive [52,53,54]. One argument for the scepticism towards public participation is that spatial plans are presented in maps and documents in technical formats that are not necessarily readily accessible to the general public. Therefore, the perceptions that planners and authorities have regarding the inability to understand the contents of spatial plans makes planners and authorities less likely to value community members’ contributions [53].

The ‘power of representation dilemma’ is one factor that hinders the delivery of social justice through spatial planning [55]. Uitermark and Nicholls [55] noted that the dilemma results from the planners’ privileged position of power and knowledge that exceeds that of the communities they represent. This superiority could result in planners sidelining community members who hold different conceptions or being selective in promoting some interests rather than others [55].

3.3.2. Technological Tools to Facilitate Public Participation and Understanding of Plans

A subsequent question that stems from the arguments above about the complexity of spatial plans is whether simplified visual representations of plans can enhance public participation and the public interest inclusion in the plans. Technology enthusiasts advocate using Public Participatory Geographic Information Systems (PPGIS) to advance democratic objectives in development at different scales [49,56]. Kahila-Tani et al. [49], however, deplored planners’ lack of sufficient knowledge and technological tools to reach larger audiences, arguing that inadequate training and tools for effective communication between planners and members of the public only make public participation accessible to a few. Others decry the under-utilisation of PPGIS, blaming it on social and institutional constraints [56].

The feasibility of successfully implementing technological solutions to public participation in the quest to capture public interest is debatable when one compares the costs to the expected benefits. Krek [48] referred to the concept of ‘rational ignorance’, which asserts that it is irrational to spend time and resources educating oneself about something so that one can make informed decisions when the costs of doing so outweigh the potential benefits that one could gain from that decision. ‘Rational ignorance’ of public interest most likely increases the community’s apathy towards participating in spatial planning, especially when they do not comprehend its significance. Such scenarios lead to planning outcomes representing the interests of privileged groups that have the means and knowledge required to participate and influence decision-making in spatial planning [39].

3.3.3. Representative Democracy

Given the lack of participation due to the various factors above, the onus to represent the interests of low-income groups and minorities is, at times, left to the planners and the elected representatives [38], whose professional competency and objectivity, however, cannot be guaranteed [41]. The factors influencing the credibility of representative democracy in planning where the interests of communities are represented by authorities and planners, as explained by Howe [32], can be summarised as follows:

• Conflict of views: These are circumstances where the planners’ views conflict with those of their seniors, elected officials, or clients. Usually, the planners’ views give way to the superiors’ views. Such situations may lead to the complete disregard of community views in cases where the planner is the only one who communicates directly with the community.
• The problem of ‘dirty hands’ is instances where certain aspects of a development project are deliberately misrepresented to achieve what the planning authority or agent assumes to be good ends. ‘Deontologists’ are particularly critical of this problem, citing its injustice to those manipulated and used to attain ends that benefit others.
• Conflict of justice is uncertainty concerning choosing between ‘deontological’ and ‘teleological’ ideas of public interest. In such cases, decisions are swayed in favour of the ethical orientation preferred by planning authorities or agents without regard to other representations.

Slaev et al. [35] also produced an additional list of problems associated with using representative democracy in planning, namely principal agent, collective action, public choice, and corruption and misuse of power problems.

Table 2. Challenges to representative democracy in planning.

Problem	Description	Impact on Inclusion of Community Interests
Conflict of interests	Conflict between planners’ views and their seniors	Disregard of community views represented by planner.There is no room for dialogue and collaboration with different interest groups; therefore, the approach is exclusively consequentialist.
Problem of dirty hands	Misrepresentation of facts to achieve certain goals	Public participation is used to legitimise preconceived ideas, leading to socially unjust outcomes of spatial planning.
Conflict of justice	Conflict between deontological and consequentialist methods	May lead to failure to recognise the importance of incorporating deontological and consequential views of public interest in the processes and outcomes of spatial planning.
Principal agent problems	Agents acting in their own interests	Excludes the public from decision-making and from enjoying the benefits of projects/programmes.
Collective action problems	Disorganisation within large groups	Unfair distribution of costs to the beneficiaries, i.e., some people will benefit from the efforts of others.
Public choice problems	High decision-making costs that prevent the public from making choices	Excludes the public from participating.
Corruption	Misuse of power by authorities	Shortchanges public resources, resulting in insufficient delivery of services by authorities.

lists the problems identified through Slaev et al. [35] and Howe [32] and depicts their meanings and possible impacts on including community interests in spatial plans.

3.3.4. Public-Centred Democracy

In public-centred democracy, locals are mobilised to create communities that actively participate in decision-making and co-formulating spatial plans. Nevertheless, focusing on a local scale, Zakhour and Metzger [57] doubted the efficacy of such arrangements, arguing that they could only succeed when backed by strong institutional support and strict adherence to the rule of law.

In Southern Africa, mobilised communities’ strategies are usually hijacked by the rich and powerful, who capture and dominate deliberations even at the lowest tiers of community planning [58]. Lizarralde and Massyn [59] asserted that business elites infiltrate community representative groups by providing incentives to local leaders or planting their dummies. The authors cited cases of gerrymandering and elite capture where local constituency boundaries were manipulated to ensure their preferred candidates were elected. The other main contention is that community engagement structures extinguish the hope of political equity by systematically de-politicising the communities they should empower. In such cases, the communities are left powerless, and they must accept the represented form of public interest delivered top-down [60].

3.4. Challenges of Quantifying Public Interest

One pertinent paradox within spatial planning revolves around the argument that attempting to operationalise public interest is insurmountable, because interests cannot be quantified easily [6]. This assertion has not been significantly challenged in the literature since Klosterman’s [61] article that mooted the possibility of quantifying public interest, arguing that any interpretation of public interest must be developed in a manner that corresponds with the term’s common usage. Klosterman’s [61] work was based on the argument that, suitably interpreted, the concept of public interest provides an empirically verifiable and defensible criterion for evaluating policies.

According to Klosterman [61], one needs to start by comprehending the types of interests that occur at the individual level to be able to meaningfully conceptualise the meaning and application of the term public interest at a policy level. One of his arguments is that it is common for individuals to be interested in things that do not benefit them or that they may not even know the value of some of the public policies formulated to advance their welfare.

For Klosterman, individual interests could also be differentiated according to the methods used to analyse and elucidate their levels. Whereas the (in)adequacy of individual concerns is mainly expressible qualitatively through levels of psychological contentment or dissatisfaction, the success levels of policies are more easily quantifiable through indicators measuring physical health and control over resources [61]. The inference of the latter statement is that the first category (individual interest) is best suited for qualitative analysis, whilst the second type is more inclined to suit both qualitative and quantitative studies; therefore, it is the type that more likely suits ideal public interests (those that are capable of being rationally defended) [62].

More detailed arguments elucidating the quantification of public interest advocate for using quality-of-life indices in formulating and implementing spatial plans [63]. Providing conceptual tools to allow planners to design accurate quality-of-life measurements, Myers recommended a five-step methodology for measuring the quality of life. Some indicators recommended are liveability comparisons, wage differentials, personal well-being, and community trends. The critical aspects highlighted in Myers’ [63] methodology include continuously monitoring the quality-of-life levels against the set goals.

The problem with how place-based comparison of life indices are applied is that “it does not measure the quality of life as residents see it” [63] (p. 354). Myers, therefore, recommended including local individuals and communities in determining the indices for measurement. The quality-of-life improvement agenda also focuses on setting goals for economic development. Such an objective could be used to bridge the gap between citizens and business elites’ interests and ameliorate inequality levels within communities.

Klosterman did not entirely disregard private interests. He suggested the importance of resolving conflicts between individuals’ legitimate interests and communities equally valid concerns. He suggested using weighting methods to determine the levels of dissatisfaction inflicted on individuals and communities by planning policies. The weighting of benefits against pain is a complex exercise which results could be defective, misleading, or biased in favour of particular stakeholders [64]. The idea of defining the public interest concept as aggregated private interests is criticised for using unorthodox means such as ‘reductionism’, ‘unidimensionalism’, ‘equal consideration of preferences’, and ‘ignorance of distributive effects’ [4,24,65]. Reductionism, in this instance, means that all individual needs and interests are regarded as equal, thus contradicting the idea of weighting. Unidimensionality refers to transforming different interests into quantitative elements capable of being measured despite the complexity normatively associated with converting individuals’ interests into quantitative entities.

In response to the criticisms above, utilitarianists resorted to the cost-benefit analysis (CBA) method borrowed from economics. For spatial planners, CBA is used to evaluate projects’ socioeconomic and environmental impact. As a tool for defending the public interest in planning, CBA underwent criticism, mainly premised on the purported incompatibility between its quantitative methods and the predominantly qualitative nature of the interests they sought to aggregate [64].

Against the backdrop of the argument that ‘inappropriate measures do not serve public interest’, Frankenstein [64] acknowledged the advantages of using scientific methods to conceptualise public interest and argued that mathematical formulas and other techniques, such as the CBA, should only be used to conduct a deeper analysis and better understand issues rather than being the sole basis for decision-making. According to Frankenstein, CBA is insensitive to the future, because it only accounts for current gains, whilst future losses are discounted. The method is also criticised for lacking fairness in determining who benefits and who pays for the costs of programmes or projects. For Frankenstein [64], mathematics in the public interest must be interwoven with other interdisciplinary studies to develop a tolerance to the complexity and ambiguity associated with the phenomenon.

In response to the socioeconomic and environmental concerns raised by critics, the CBA was modified to what came to be known as the Planning Balance Sheet (PBS) and, later, the Community Impact Evaluation (CIE) [8,66]. PBS modified the definitions of certain critical concepts borrowed from the CBA and the accounting profession (from which the term ‘balance sheet’ originated) to better align them with the principles of spatial planning. Assets, liabilities, equity, flexibility, trade-offs, and participation are some redefined vital concepts that directly relate to defining and including interests in planning [67,68].

A synthesis of the classification of interests [61], quality-of-life indicators [63], and PBS and CIE [67,68] offers insights into the development of methods that can be used to effectively capture, measure, and depict public interests for spatial planning. The focus should be on developing exclusive perceptions to benefit the current and future generations. The idea is in sync with the main quality-of-life improvement goals of spatial planning, which are inherently futuristic.

4. Discussion

This section discusses and synthesises the literature to develop a synopsis of the interpretations and applications of public interest in spatial planning. The discussion is guided by two themes: defining the characteristics of the different categories of ‘public’ that constitute the planning subjects and interpreting the meaning of ‘interest(s)’ in spatial planning.

4.1. Interpreting the Meaning of Public in Public Interest

Spatial planning largely derives legitimacy from a claim to represent the public interest [4], which is not a homogeneous entity bound together by identical or common interests. Some definitions of public interest refer to something that is for the collective good of all citizens [40]. Such unitary views assume a possibility of identifying some homogeneous factors that can bind heterogeneous individuals and communities into a single public. It is, therefore, essential to understand the composition and characteristics of groups of people that constitute the ‘public’. This study identified four main groups: individuals and ordinary community members, business elites, politicians, and planners. Each group has its perception of public interest, as discussed below.

4.1.1. Individuals and Communities

The study’s primary focus was the individuals and communities group, because the literature review findings contend it is the most underrepresented and marginalised [25,69]. Ironically, state-driven planning claims that it protects this group from demeaning factors, such as market failure [70]. The critical question we pose is how is it that those that spatial planning claims to represent become the victims in the same planning processes? The literature demonstrated how power could be manipulated and diverted to represent or reinforce the interests of more powerful individuals or groups [35,41]. The manipulators employ political strategies such as tokenism in public participation [50], elite capture in representative democracy [60], and the problem of ‘dirty hands’ in planning’s representative democracy [33] to ensure that communities validate the planners’ and authorities’ interests.

Other factors affecting communities’ participation in spatial planning are rational ignorance, misjudgement, and technical ignorance. These are problems related to communities’ lack of knowledge on planning issues. Consequently, communities fail to appreciate the value of public participation, make informed judgements, understand technical presentations, and cooperate on community development processes.

We argue that the most apparent solution to the problem of insufficient knowledge is that communities need to be educated and encouraged to participate in planning processes. A more contextualised solution may be more appropriate after considering the following concerns: One, can the cost (in terms of money and time) of empowering a community with technical skills be justified by the expected benefits from a more participatory planning process? Two, do all community members or representatives have the basic skills that would enable them to comprehend the technical complexities of spatial planning?

Our argument is that the focus should be on devising strategies that best capture and represent communities’ interests in spatial plans rather than seeking to turn community members into pseudo-planning proxies. The planners should steer the process with services such as interpreting the meaning of planning objectives and concepts and predicting the possible outcomes of selected policies to benefit the non-technical stakeholders. However, in so doing, care should be taken to ensure that the planners and authorities do not exploit these concerns into dismissing the genuine interests of communities from being included in the planning processes.

4.1.2. Planners and Authorities

The planners and politicians groups are the other groups that interact directly with interested and affected individuals and communities. The power of representation dilemma impacts both groups, as they represent communities within their respective technical and political roles. We argue these dilemmas could be minimised by creating shared platforms for decision-making that equitably distribute power amongst political, community, and technical actors. This could be achieved using, for instance, Rosen and Painter’s model [71], which states that sustainable community power can be achieved when practitioners and authorities develop long-term participation models supported by capacity building and resource sharing.

We argue the other issue concerning the planners’ attitudes towards what they see as poorly informed and uneducated contributions of the public interest could be addressed in the following manner: one, streamlining the specific roles of communities and giving guidance on the format, type, and quality of expected community contributions; two, factoring in participation and community interests into the process and the presentation of plans using statutory standards or systems; three, having unambiguous protocols for local interests inclusion would serve to not only guide the process but would also shorten it; four, decentralising decision-making in planning to local-level platforms discussed previously.

4.1.3. Business Elites

Business elites comprise well-represented people in development processes, because they have the resources and power to influence decisions. Most of the literature reviewed in the present study only highlights the negative aspects of the business elites group. Consequently, the literature undervalues some concerns expressed by business stakeholders, such as the claim that their investments enhance the quality of life [28]. These negative attitudes could partly contribute to the business people’s recourse to unorthodox tactics that influence spatial planning decision-making. Such tactics include elite capture, bribery, and gerrymandering. The other concern is that the planning literature mostly views the business sector as a homogeneous group, yet there is a vast resource gap between business elites and local businesses. It, therefore, appears that the local business group that should be accordingly classified as part of the communities is usually given less attention in planning discourses.

The reviewed literature has shown that one area demonstrating divergent views (of the groups above) on public interest is mega projects and new town developments. Such developments are either labelled as beneficial through, among others, promoting economic growth [72] and therefore regarded as public interest-enhancing projects by planners and business elites or they are condemned by the community members as anti-public for causing displacements and depleting natural resources [43,44,47,73]. What is important from our perspective, though, is that the appraisal of such projects be comprehensive enough to include all the ethical, socioeconomic, and justice considerations.

4.2. Interpreting the Meaning of Interest(s)

We argue that, although the words ‘interests’ and ‘interest’ can be used in the plural sense, they have different meanings. ‘Interests’ align more with the private interests of individuals, organisations, and communities. In contrast, ‘interest’ relates more to policy-level definitions of the public interest phenomenon. We contend, therefore, that the public interest conundrum for planning practice revolves around answering the question ‘What makes interests public?’.

There are no simple responses to this question. For instance, several conceptualisations of the public found in the literature reviewed have been more concerned with describing the concept in substantive or procedural terms or in aggregative versus deontic terms [4,12,74]. Although these provide a broad basis for framing the public interest in planning, such studies do not provide linkages with the hierarchical levels of spatial planning. This is in line with our observation that most planning systems are designed hierarchically, where lower-level plans are required to be subordinate to higher-level plans [19,25,39].

Data on individual and community members’ interests can be collected and included in the drafts of lower-level plans at the community and neighbourhood levels [7,8]. However, the chances of such information being included in the final plans are slim, as they will be required to align with the policies outlined in the higher-level plans [19,25,39]. Therefore, we recommend that planning systems be transformed through a framework that outlines the procedures and linkages between plan levels and the categories of interests.

The literature on zoning describes its purpose and usefulness in defending property rights, rights to development, and protecting citizens from the negative externalities of development [22]. However, the discourse on zoning does not discuss the methods and the possible connection between public interest and the zoning plan. We argue that this gap opens the way for further research that could consider the production of public interest maps. Such maps could be used as overlays that inform the land use zones’ design and mapping exercises. Public interest maps would demonstrate the inclusion of public views in planning and be useful yardsticks for plan evaluations. Public interest maps could also help simplify spatial plan presentation formats, dispelling concerns about plans being too intricate for ordinary community members to understand.

5. Conclusions

This article exposed public interest’s vulnerability to abuse through manipulation and misrepresentation in urban settings with diverse stakeholders with different and potentially conflictual interests. The literature shows how different ideological and ethical perceptions of public interest have contributed to complicating its application in spatial planning. We have attempted to unpack and discuss the different types of ‘publics’ that can be referenced by planners and authorities to legitimise decisions made genuinely or deceitfully in the public interest. Evidence suggests that individuals’ and communities’ role in determining the public interest in spatial planning is minimal. For that reason, we have offered some options and approaches for incorporating mechanisms that protect the vulnerable members of society from marginalisation. The main recommendation points towards the need to develop a framework for guiding the stakeholders in spatial planning on effectively including community interests in the plans. Such a framework must be flexible enough to align different interpretations of public interest with their specific urban contexts.

We specifically propose linking the conventional zoning maps used in spatial planning with thematic maps that depict community interests in visual formats to improve the inclusion, transparency, and presentation of public interest in spatial planning. Both the framework and the thematic mapping would contribute to bridging the knowledge gap between planning as a practice with technical aspects and the non-technical recipients or beneficiaries of planning processes.

For developing the framework and public interest map mentioned above, we propose that case study-based empirical research be conducted to answer the following questions:

• How do individuals, local interest groups, community-based organisations, and the business community view and interpret the application of public interest in spatial planning and development?
• What is the meaning of public interest according to planners and authorities, and what is their perception of the concept’s role in spatial planning and development?
• How do the spatial planning documents capture and depict the diverse interests of individuals, local interest groups, community-based organisations, and the business community?
• What factors influence the levels of public interest inclusion in spatial planning?

Unpacking the different stakeholders’ views and interpretations of public interest would lead to compiling thematic public interest maps depicting similarities and differences between the diverse interpretations and the contents of spatial plans. This analysis would culminate in a framework for including diverse interpretations of public interest in spatial plans.