Environmental Economics Research Paper- Featuring Villanova Professor Chris Jeffords

Environmental Economics:

Theory, Rights, and Policy

Nicholas Djoulia

April 2026

Abstract

This paper provides an overview and analysis of environmental economics, an interdisciplinary field that examines the relationship among markets, policy, and human rights. Building on economist Chris Jeffords's research, it argues that traditional economic models are insufficient to describe societal issues, failing to account for equity constraints, demographic disparities, and humanity's core values. This argument is expanded on throughout the paper through the breakdown of 6 interconnected substructures: the market failure theory and its impact on policy; the Kuznets Curve, along with the Jeffords and Thompson minimum consumption modification; the global record on environmental rights constitutionally and the difference between the legal frameworks and the real-world outcomes; the extent of environmental concern and the impact of pollution; the theoretical economic viewpoint vs. the policy implementation of congestion pricing; and and the global link between developmental finance and environmental conditions. However, policy implications, from carbon taxes to congestion pricing, face significant challenges despite proposed benefits.

1. Introduction

In June 2024, New York City's congestion pricing program, a pioneering effort with traffic restrictions in Manhattan, was halted weeks before implementation by an executive order citing equity concerns. Weeks before its official implementation, an executive order halted it. The federal government's rationale was clear: equity. The federal government feared the toll would unfairly burden out-of-borough commuters and local businesses. In contrast, congestion pricing was justified by improved air quality through increased use of public transportation, leading to higher economic output for New Yorkers by clearing roadways for a strained transit system. 

This scenario reflects a central focus of environmental economics: the gap between economic theory and its intentions, and what the policy will deliver in practice. That gap between the legalities and the realities, between economic efficiency and demographic equity, is the primary focus of this paper.

Professor Chris Jeffords's research demonstrates that economic models and tools have limitations, underperforming in practice on topics like human rights, inequality, and institutional capacity. His findings show that constitutional environmental rights foster positive outcomes across demographics, supported by functioning institutions and enforcement. This connects to the congestion pricing paradox, with outcomes heavily dependent on enforcement and implementation.

The paper’s central claim is that environmental economics yields the best results when it incorporates rights, equity, and institutional capacity into strict economics, thereby avoiding political trepidation. A carbon tax without demographic concerns will fail politically; a constitutional provision without proper enforcement will fail in real-world scenarios; a congestion toll without consumer alternatives will fail in both respects. In each scenario, theoretical economics checks out, but policy implementation is incomplete.

II. Foundations of Environmental Economics: Externalities, Instruments, and Gaps

1. Externalities and the Corrective Policy Toolkit

Environmental economics is founded on the idea that markets fail to account for environmental protection because emissions and waste impose a burden on consumers and the public. This negative impact was classified as an externality, a cost bearing on third parties, by Pigou (1920) through his conceptualization of the Pigouvian Tax. The tax is a corrective measure designed to charge polluters the amount equal to the social cost they impose on society. Some confuse this with an externality itself, while it is really a mechanism that aims to correct it. This social cost applies to carbon emissions, one of the most contentious environmental and societal issues of the last century, which originated primarily from the Industrial Revolution in the late 18th century (World Bank, 2024). Prices range from under $20 to over $200 per ton, depending on location and damage (EPA, 2023). Strictly economic changes to the industry cannot resolve this issue; policy has to be implemented from the top down

Whether at the national, state, or local level, three policy families are involved in effecting change. Command-and-control regulations set standards across the board. An example of this is the Clean Air Act of 1963 (updated in 1970), which established government mandates for companies on pollution and emissions (EPA, n.d.-b). With this kind of policy, measures are enforceable; however, not cost-effective for all firms, and there is no incentive for firms to follow them. This could lead to economic risks, such as a slowdown of revenue if firms cannot achieve positive margins under the policy. Price-based instruments, such as a tax or a subsidy, are more cost-effective because they set a price for a specific element of a product in an industry, while allowing flexibility by imposing a tax on noncompliance.

An example would be the federal government setting a $50-per-ton price for CO2 emissions when emissions exceed a certain threshold. Some firms will pay the tax if they deem it cost-effective, while others will remain below the set emissions limit to avoid it. This type of policy still gives firms breathing room economically while promoting an environmentally friendly agenda. Information-based instruments work by providing people with better information about current environmental issues, enabling them to make sound financial and societal decisions. For example, the Emergency Planning and Community Right-to-Know Act of 1986 mandated that factories and industrial facilities publicly report the amounts of toxic materials they released into the environment, whether into water, air, or land (EPA, n.d.-c). This is a way to protect the public from industry's environmental abuses by requiring businesses to provide the public with better information. An important barrier to recognize with this policy is consumer ignorance and the public's overall willingness to accept the information provided to them, rather than a direct externality they face. In general, these policies aim to correct environmental market failures by influencing the behavior of both businesses and the public, leading to better outcomes for society, both socially and environmentally.

2. The Economics-Policy Gap

In terms of a strict economic focus, the efficient policy is rarely the politically sound one. Three structural gaps in our system help examine this: losers in markets and politics organize and band together to combat winners in both fields (political economy); economically optimal policies impose costs unequally on the economically and politically disadvantaged, creating friction in society even when welfare and governmental programs aid the aggregate (distributional conflict); and enforcement capacity of policy by governments varies dramatically across nations (implementation capacity). These political-economy interactions are analyzed throughout Jeffords’ research.

3. Public Goods, the Commons, and Private Bargaining

Public goods theory explains that some goods and services are not provided by the free market, which forces governments to step in to provide them, such as welfare. This theory explains why clean air and climate stability cannot be adequately supplied by markets in a capitalist society: since these goods are non-rival and non-excludable, individuals can reap the benefits without contributing, echoing the classic free-rider problem in our society. This theory explains why clean air and climate stability cannot be adequately supplied by markets in a capitalist society. Since these goods are non-rival and non-excludable, individuals can reap the benefits without contributing, echoing the classic free-rider problem in our society. This leads markets to be apprehensive about supporting certain sectors of society, such as clean air and broader environmental protection. Hardin (1968) examined this dynamic in "The Tragedy of the Commons," arguing that individuals utilizing shared resources will eventually deplete them without governmental regulation. Economist Elinor Ostrom challenged this stance through her work on common-pool resources, providing strong support for the argument that the free-rider problem is not inevitable and that government is not always necessary to foster effective institutions, emphasizing the role of private enterprise under the right circumstances. This concept links directly to Jeffords' work, in his finding that constitutional rights require effective institutions to support their provisions. Similarly, Economist Ronald Coase (1960) argued that private parties can conduct business and financial transactions (private bargaining) when property rights are defined, and transaction costs are low. Unfortunately, this concept often does not hold because the aforementioned conditions are absent in real-world environmental markets.

III. The Environmental Kuznets Curve and Its Limits

1. The Inverted-U Hypothesis

The Environmental Kuznets Curve, abbreviated as EKC, examines the relationship between per capita income and environmental degradation: as a country’s income rises, environmental degradation worsens, then improves, forming a U-shaped graph. Preindustrial nations have worsened their environmental positioning, then peaked during the industrial period, and declined on the post-industrial, “wealthy” side of the graph. Grossman and Krueger (1991) provided fundamental support for this pattern: they found that sulfur dioxide (classified by the EPA as one of the six criteria air pollutants) and particulate matter concentrations peaked and then declined near average per capita income levels of around $ 4,500 (in 1985 dollars) (EPA, n.d.). This finding showed a quantifiable turning point in which environmental development is a byproduct of further economic development, supporting the EKC hypothesis with empirical, observable data rather than relying solely on theory.

However, this hypothesis is more fragile in practice than it might appear. CO2 emissions, for example, do not follow the inverted-U pattern across multiple income ranges, partly because wealthy nations have not curbed emissions and cleaned up "dirty" production. At the graph's center, estimates vary across many studies, and the lack of a tangible mechanism connecting growing wealth to environmental progress makes the "simple" theory structurally questionable.

2. The Minimum Consumption Floor

Jeffords and Thompson (2019) modify the EKC model by introducing a theoretical minimum consumption requirement. This requirement establishes that a baseline level of consumption is necessary for households to factor environmental concerns into their financials. Below this baseline, environmental concerns are theoretically not on households' financial docket, with their preferences for these issues below the effective societal demand. Above the baseline, environmental concern is economically feasible, enabling households to meet the societal demand for environmental causes. The result is that the EKC's apex is further to the left in practice than in theory, due to environmental improvements arriving earlier and being combined with the minimum baseline environmental policy.  

The policy implication challenges the "grow first, clean later" logic because distributional policies enable people with low incomes to meet a baseline of financial stability, not through welfare programs, but through environmental policy. Environmental policy improves working and living conditions by reducing emissions and congestion, leading to better job opportunities and a higher quality of life. To support this environmental policy and progress, economic growth must be sustainable, along with the institutional capacity to uphold that progress.

IV. Constitutional Environmental Rights: Law, Data, and Outcomes

1. The Global Spread of CERs

Fewer than 10 nations around the globe had explicitly stated constitutional provisions supporting environmental rights in 1970, but by the early 2020s, nearly 100 nations had adopted environmental rights into their constitutional framework (Boyd, 2012). An important note, Gellers (2018) specifically states that biology, political science, and statistical analysis have played far-reaching roles in the expansion of these rights. These constitutional rights, abbreviated as CERs, include non-quantitative and tangible measures, such as guaranteeing the right to clean air and water, and measures maintaining a nation's environment, as well as procedural measures, such as altering the nation’s justice system to accommodate environmental concerns.

Jeffords's (2021) quantitative analysis found that nations with CERs achieve substantially higher levels of clean water, sanitation, and emissions reduction than nations that lack them. His cross-national analysis uses outcome variables, including access to sanitation and water sources and decreased CO2 emissions, and finds strong statistical significance between CER adoption and material gains in environmental conditions. However, nations with CERs that have the institutional capacity to sustain them achieve the greatest levels of environmental progress. A high-quality judicial system, combined with civil society and the rule of law, helps enforce CERs. On the other hand, nations with lower income and structural capacity, even with the same constitutional provision, achieve minimal progress.

2. The Implementation Gap

Gellers and Jeffords (2021) study the implementation gap, determining the significant national shortfall between constitutional rights and what governments can enforce. Failures in Monitoring, without data capacity to assess environmental compliance and enforcement, and without formal capabilities to compel compliance or participation, contribute to the gap. 

Gellers and Jeffords analysis (2019b) of the Asia-Pacific region confirms that this pattern, the gap in implementation, is not just the outcome of a legal problem, but a combination of problems stemming from failure of economic information distribution, transaction costs, and rent-seeking dynamics. With that being said, the implementation gap is not only a systemic legal issue but also a major economic challenge.

V. Environmental Inequality: Concern, Burden, and Distribution

1. Environmental Concern as a Luxury Good

Jeffords, Thompson, and Gwinn (2019) used Google Trends data to show that wealthier US households use the internet to research environmental issues much more often than lower-income households. This has led economists to consider environmental concern a luxury, with rising income equating to more access to the means to perpetuate environmental change. The political economy implications reason that policy will reflect the wishes of those with the most financial means, the elite. Moreover, this policy will reflect the wishes and voices of those who are least likely to face environmental hardships, such as the negative effects of pollution, because of the wealthy’s inherent access to better living conditions and economic opportunities.

2. Unequal Burdens and Revenue Redistribution

The environmental justice academic community confirms a fundamental inequity: minority and low-income households bear pollution and environmental consequences disproportionately. For example, when it comes to particulate matter exposure, respiratory and cardiovascular disease, mortality rates, and cognitive decline in children can be traced to the inability to avoid polluted environments (Di et al., 2017; Sunyer et al., 2015). Moreover, the truly unfortunate phenomenon is that this harm compounds across generations, affecting entire communities for many years to come (Banzhaf et al., 2019).

Environmental policy elements, at times, fail to help communities facing compounded inequalities. For example, carbon taxes, through their regressive structure, burden many because lower-income households spend a larger share of their income on energy than wealthier households do (Hassett et al., 2009), facing rates that undermine their financial integrity on a broad scale, such as jeopardizing their ability to pay for other essentials like food and clothing. To correct this, a revenue design, where a fee-and-dividend revenue return works as a uniform lump sum, can be progressive (tax rate increases with income) in net terms, but this could force distributional analysis to occur to survey policy before widespread implementation, not later on, to avoid harming the people and communities the policy was meant to benefit (Cronin et al., 2019).

VI. Congestion Pricing: Economic Theory and Political Reality

1. The Congestion Externality and the Optimal Toll

Roads and highway systems have been a common-pool resource, used without restriction by society. In this system, drivers interact in a congested network that experiences internal delays, with a couple of road-goers causing a traffic backlog without experiencing it themselves. This is called the congestion externality. Pigouvian theory can be applied, concluding that each driver emits a marginal external cost to the system they drive in and should be charged for it. Walters (1961) and Vickrey (1969) developed a formal calculation for this charge, commonly referred to as a "toll" fee. AC(q) is defined as the average trip cost at traffic amount q, yielding a marginal societal cost:

MSC(q) = AC(q) + q × [dAC/dq]

The second term, (q[dAC/dq]), is an externality, the cost that falls on another person that typically goes unaccounted for, representing the additional delay per driver multiplied by the number of drivers present in the system (the road). The optimal toll in a perfect world is set equal to the cost you impose on others, but is calculated using the target traffic level rather than today's. The Bureau of Public Roads (Bureau of Public Roads, 1964) aids in calculating the cost you impose by measuring how travel time rises with traffic volume, (dAC/dq):

dAC/dq = Travel time = Free-flow time × [1 + 0.15 × (volume/capacity)^4]

In the aforementioned equation, the fourth-power relationship indicates that the cost you impose on others rises steeply near the system's maximum capacity, so small reductions in the volume of cars on congested roads greatly reduce travel time for drivers. Vickrey’s model extends the aforementioned model to a dynamic setting: a toll that accounts for time-varying updates to the toll price, accurately charging drivers for the cost they impose on the system. For example, Singapore’s ERP2 system demonstrates this in practice by updating tolls every 30 minutes based on changing road conditions (e.g., traffic volume). Further examples of congestion pricing initiatives will be presented in the next section (Land Transport Authority, n.d.).

2. Global Evidence: London, Stockholm, Singapore, New York

The international record on congestion pricing is clearly correlated with efficiency gains in markets. London’s 2003 Congestion Charge reduced London traffic by 15-20%, and reduced travel time by 30% (Transport for London, 2007), while generating over £130 million in annual revenue for England’s transit system. In Stockholm, a time-varying tax, permanent since 2007, reduced inner-city traffic by 20-25% and CO2 emissions by about 10%. Taken together, Eliasson’s welfare analysis (2009) and Böjesson et al. (2012) affirm that net social benefits are positive after accounting for administrative costs, indicating a true positive impact on communities from congestion pricing.

Back to the Singapore example, the Singapore ERP, introduced in 1975, demonstrates that dynamic congestion pricing can operate without political interference when integrated into traffic policy (Asian Development, 2016). Through the implementation of variable tolls, reinvestment in public transit alternatives, and parking policies, this multi-pronged approach prevented political backlash. This multi-pronged approach to time-varying congestion pricing prevented political backlash that would typically topple single-pronged initiatives. 

In New York, their 2024 Program, a $9 base toll that projected $1 billion in annual revenue for the MTA, was halted by an executive order after years of legislative approval and environmental review. The pause itself signals a widespread and systemic gap between congestion pricing and environmental policy. Jeffords identified this trend with constitutional environmental rights, which suffer despite broad societal support.

3. Regressivity, Revenue, and Environmental Co-Benefits

The distribution of taxes from rich to poor has long been a source of conflict between regressive and flat tax rates. The regressive argument is that a flat toll takes a larger share of income from lower-income drivers, but a full welfare analysis shows that the benefits outweigh this argument. Four corrections to this stance need discussion:  

First, congestion itself does not automatically harm low-income bus riders disproportionately compared to wealthier riders. London’s congestion charge in 2003, which critics argued was a regressive toll (individual drivers were forced to pay higher tolls than before its implementation), failed to account for the fact that most low-income people traveled by bus. The 30% decrease in travel time directly benefited low-income travelers.  

Second, Parry and Small's research shows that when toll revenue increases and is reinvested in public transit, the overall effect can be progressive. The initial toll payment is regressive, targeting individual drivers, but expanded bus services and rail services with reduced fares for lower-income riders benefit lower-income households more.

Third, peak travel-time drivers in business districts skew congestion data toward higher-income demographics, weakening the regressive argument. The toll data show that the more expensive toll zone falls within this area, predominantly impacting wealthier drivers. Lower-income drivers bear a smaller share of the toll burden because they do not use this zone for work.

Fourth, Goulder's framework shows that toll revenue can replace inefficient labor taxes, fostering economy-wide efficiency gains. If toll revenue allows governments to lower income taxes, the distributional impact can favor lower-income households, even if the toll appears regressive.

4. Political Economy: Why Theory Outpaces Adoption

Sixty-plus years of economic thought have yielded a few operational schemes for congestion pricing. The concept of loss aversion, the pain of loss hurts greater than the benefit of winning, as examined by Kahneman and Tversky (1979), explains that when drivers experience the toll on a trip that was previously free, opposition arises socially and politically from taxi fleets, trucking unions, and parking policy advocates. This is how change in the political economy can be enacted. Also, diffusionary benefits stemming from the additional toll, such as faster travel and cleaner air, are delayed and not concentrated, leading to further opposition towards the implemented tolls.

These ideas map onto the luxury-good concept: voice in politics is distributed across different income classes, not through environmental concern. Stockholm's success shows what it takes for congestion pricing to remain politically relevant: let the public experience congestion pricing before a vote, ensure stable transit alternatives, and clearly show how revenue is allocated. New York's last-minute cancellation of its congestion policy shows that without careful politics, trust and support can erode.

The failure of New York's congestion pricing can be understood through Jeffords' research on the minimum consumption threshold. The minimum consumption threshold (see section III) examined by Jeffords and Thompson (2019) indicates that households below or near the consumption minimum cannot afford to take environmental concerns into political consideration, as they are financially constrained. However, it was the outer-borough commuters, not as wealthy as the inner-borough commuters (in Manhattan), whose political pressure helped halt the congestion pricing initiative. The luxury-good findings forecast that the wealthier population would produce the strongest opposition to congestion pricing, while facing the least environmental harm. This lopsided power structure creates an environment where populations that win gain the most while lacking the necessary resources for change. The populations that would be least affected have the greatest impact and thus do not foster change. This is what we can call a cross-cutting dynamic, with the minimum consumption requirement supported by the lower-income population. At the same time, the luxury-goods phenomenon keeps political power in the hands of the least needy, helping to explain why congestion pricing is politically ineffective despite its positive environmental and economically efficient outcomes.

VII. International Dimensions: Development Finance and Environmental Conditions

1. China’s Development Finance in Africa

Gellers and Jeffords (2019) explore the African continent’s environmental situation. They pondered whether environmental conditions in African countries influence where China chooses to invest on the continent through its 21st Century “Belt and Road” initiative. They analyzed China's investment choices and found that pollution levels, resource availability, and ecological conditions are important indicators of where China invests. These concerns persist even after addressing economic and political issues. Since it is clear that China pays attention to environmental concerns, this challenges the assumption that environmental factors are secondary to commercial motivations and economic concerns, and that they are merely a consequence of the decision-making process rather than a factor in it.

2. Green Finance and the Evolving Landscape

Building on the aforementioned analysis of China’s investment choices, China has adopted the Green Bond Standards and the safeguards established by the Asian Infrastructure Investment Bank to enhance its environmental profile further (AIIB, 2016). Whether these commitments have tangible effects remains undetermined, and Gellers and Jeffords' framework will investigate this issue further.  

VIII. Synthesis: Towards Rights-Integration

1. Three Recurring Structure Failures 

Three structural failures in Environmental Economics recur across domains: the market pricing failure, the implementation failure, and the equity failure. The market pricing failure imparts pollution expenses on parties not involved in production, while the implementation failure creates distributional burdens that lead to widespread resistance. The implementation failure: legal and well-designed policies often fail to produce their intended results because opponents of the policy concentrate and diffuse the benefits (see section VI for more detail). This can create distributional burdens that lead to widespread political resistance and weaken enforcement capacity. Jeffords explores and documents this phenomenon in his investigation of constitutional rights, and New York also documents it in its congestion pricing. The equity failure: standard environmental-economic models attempt to optimize welfare. At the same time, lower-income populations have the least impactful political voice and bear the greatest environmental burdens in a system that is supposed to aid them. 

2. Rights, Equity, and Institutional Capacity

The paper argues that environmental economics yields better analysis and outcomes when rights, equity, and institutional capacity arise internally within the model. Jeffords and Thompson’s EKC modification demonstrates this concept in context: the EKC trajectory is not fully captured by income alone; rather, it combines income information with distributional policy to yield an effective estimate. Jeffords also worked on constitutional rights research that further demonstrated this through a governance lens: institutional capacity cannot be found solely in a constitutional text, but is a cause of outcomes in practice through implementation and governmental support.

The analysis of congestion pricing shows that evaluating pricing using Pigouvian theory alone overestimates policy adoption and underestimates political fragility. This lesson is generalized across carbon pricing and protected area policy: the path from purely economic analysis (theoretical) to lasting policy outcomes through political economy, distributional initiatives, and institutional capacity.

IX. Conclusion

Environmental economics is most useful as a framework for understanding situations in which environmental progress is politically feasible and institutionally durable. Jeffords' research models the field's aims: quantitative rigor, human rights implementation, and a political economy examination of why populations most affected by environmental degradation are distributionally harmed and underrepresented.  

Collectively, Jeffords' works demonstrate that the implementation gap is a central economic concern of environmental policy. The minimum consumption threshold determines who can afford environmental action, the luxury-good concept determines who is effectively heard, and institutional capacity determines whether environmental rights can be implemented and sustained. Environmental economics, as presented in this paper, must continue to model the aforementioned implementation constraints with the same tenacity it has shown in addressing externality concerns and taxation (Pigouvian). The field's potential in analyzing and solving societal issues is not the question; rather, it is the field’s ability to bind theory and lasting policy, which Jeffords’ work emphasizes to a large extent.

Future directions for environmental economics include cross regional comparisons of congestion pricing implementations that build on Jeffords’ comparative rights framework to analysis policy; behavioral research on how political and societal framing of issues greatly affects public support for pricing initiatives; mixed-methods work in combination with cross-national quantitative work with qualitative case studies to accurately identify the practical means of converting constitutional rights on paper into real-world outcomes; and updated analysis of Chinese development and investment profile using the Gellers and Jeffords framework to assess whether green finance promises have resulted in measurable environmental improvements. The tools that can aid this - Pigouvian taxes, cap-and-trade, constitutional rights, congestion pricing - are well developed and are currently in the works politically around the world. The challenge Jeffords' work highlights is sustaining the effectiveness of these tools in the complex landscapes of actual societies. 

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