Abstract
With pertinent reforms in existing legal dynamics, judicial opinions and scholarly commentary have increasingly converged to bring global environmental issues to the universal forefront of international discourse. By facilitating dialogue, dispute resolution, and the development of customary international norms, these forums enable states to engage in cooperative frameworks. The normative legal notions though solemn and prudent while drafting remain underdeveloped and untouched. One of the core reasons for this ignorance is jurisdictional ambiguity. Issues like trans-boundary environmental harm breakthrough the thresholds of geographical limitations. States often rely on weak international cooperation and thus success towards uniform application of legal interpretation remains an illusion. Transboundary environmental damage has become an urgent issue in the global legal system, particularly in a time when there is rising environmental crisis, global warming, and transboundary industrialization. This paper critically evaluates the conceptual, legal, and institutional obstacles to holding states accountable for transboundary environmental harm. Moreover, the shattered structure of the international environmental law generates inconsistencies and non-uniformity in its conduct and application. The article also questions the function of procedural barriers to claim-making by affected states and non-state actors, especially in fora like the International Court of Justice (ICJ) or arbitration tribunals. The study highlights the fallacies in international environmental law statutes and how liability and responsibility are looked upon differently in the global arena.
Keywords
Transboundary, state responsibility, environment impact assessment, no harm rule, due diligence, global environmental liability, precautionary principle.
Introduction
International law has undergone numerous changes and is very different today from the traditional conception. Our planet faces innumerable challenges that can be tackled only through international cooperation by various stakeholders. Acid rain, loss of biodiversity, ozone depletion, transmission of toxic waste and pollution of rivers are only some of the issues that are faced by the international community. (Sands, 2003) The impacts of industrialization, commercialization and globalization is faced by not only the host nation but also the world as a whole. Thus, the activities of one state have brutal impact on other states as well, leading us to the legal issue of “trans-boundary harm.” Transboundary environmental harm is an environmental problem that crosses political and geographical boundaries affecting multiple countries or regions causing loss of biodiversity, degradation of shared resources, reduced agricultural productivity also leading to strained geopolitical relations which might affect sovereignty and peace in the global sphere.
Climate change is also another factor that gives rise to trans-boundary harm. Uncertainty from climate change impacts shared resources in unpredictable ways. A nuanced understanding of international treaties, conventions and precedents are required to form an opinion about the liability of a state in such situations.
Methodology
This study embraces “analytical research mechanism” coupled with “doctrinal research mechanism” Throughout this study the author has simplified complex legal issues revolving around state responsibility and transboundary harm with an aim to improve the generic understanding of cross-national dispute resolution with preference to international environmental issues erupting worldwide. This approach helps to investigate the effectiveness, sufficiency, and confines of current legal norms in addressing states’ liabilities and obligations for cross- border harm. The research study will be mostly on doctrinal legal research, where statutory documents like the International Law Commission’s Articles on State Responsibility, the Draft Articles on the Prevention of Transboundary Harm from Hazardous Activities, and applicable provisions of UNCLOS, and other sectoral treaties are analyzed. Secondary sources like articles, commentaries, law journals and institutional publications offer critical lacunas, contradictions, and reforms in existing legal systems.
Review of Literature
The dialogue on transboundary environmental harm and state responsibility has developed due to the incongruity of judicial opinions, scholarly analyses, and normative frameworks that were proposed but never applied or discussed in depth. While international law recognizes state responsibility principles, practical enforcement and clarity remain obsolete. The stance of state liability, being one of the most undiscovered areas of law, is far from the limelight of social justice and economic rights. Ehteshamul Hoq and Amdadul Hoque critically examine the doctrine of state responsibility within the borders of international environment law, emphasizing its inconsistent application across regimes. Although the United Nations Convention on the Law of the Sea (UNCLOS) offers detailed obligations concerning marine pollution as per Art 192- 194, it fails to specify the degree of liability or effective dispute mechanisms, particularly for non- party states, and hence limits its utility. (Ehteshamul Hoq, 2019). Moreover, the absence of a unified environmental legal system, makes responsibility regime-specific and dependent on overlapping treaty structures. Nayantara Ravichandran in her work explores how international environmental law freezes the traditional notions of absolute sovereignty, especially in the context of transboundary harm. Through a series of ICJ judgements she illustrates the firm requirement for the states to conduct environmental impact assessments (EIAs) and respect the fundamental principle of sustainable development with regards to intergenerational equity. (ravichandran, n.d.) Dr. Christina Voigt provides a comprehensive doctrinal framework addressing environmental accountability, she views state responsibility and liability as distinct but interconnected elements. She acknowledges the ILC’s 2001 Articles on State Responsibility and the 2001 Draft Articles on the Prevention of Transboundary Harm from Hazardous Activities as foundational texts but emphasizes that they are not binding treaties. The absence of consistent case law further weakens the operationalization of state accountability, especially in the context of long-term, cumulative environmental damage. (Voigt, 2021). Collectively, these works underscore both progress and persistent deficiencies in international legal frameworks addressing transboundary harm.
Applicability of International Environmental Law
Today, international environmental law operates on the premise that states are custodians, not owners, of the environment, bound by both sovereign rights and transboundary duties. This evolving body of law seeks not only to protect biodiversity and regulate emissions but also to reintroduce the age-old wisdom of coexistence, accountability, and harmony, albeit through a secular, juridical lens. However, there has been a need for the development of law to be quicker and more flexible than in the past considering the various environmental concerns. (ravichandran, n.d.) Thus, there has been the adoption of new concepts and principles that account for sustainable development. (P.W. Birnie, 2002) These are reflected in ‘soft law’ instruments, and are important in environmental law. Instruments such as the Rio Declaration, 1992 and the Stockholm Declaration, 1972 are relevant to the extent that they restrict state practice and hold great relevance in the formulation of customary international law. (Atappatu, 1998)
Legal basis of transboundary environmental harm
Under customary international law, states are obligated to not inflict damage on or violate the rights of other states. In international environmental law, this obligation has been recognized as
“No-harm rule” as it’s assumed that every state must respect the sovereignty and authority of another state. According to Sec 2(c) of Prevention of Transboundary Harm from Hazardous Activities 2001 “transboundary harm” means harm caused in the territory of or in other places under the authority or control of a State other than the State of origin, whether or not the States concerned share a common border. This can be better understood with reference to the Trail Smelter case, where the court held that, no nation has the absolute right to use or permit the use of its territory or resources in such a manner as to inflict injury by fumes in or to the territory of another or the properties or persons. (Nations, 1950). Contributions by the International Law Commission have been quite extensive yet do not hold primary importance in international study. Substantial progress was made in 2001. These articles laid out detailed obligations for states, including conducting environmental impact assessments (EIAs), notifying and consulting affected states, monitoring hazardous activities, and taking preventive and control measures. Drawing from prior legal instruments and expectations concerning transboundary environmental risks frameworks such as those regulating the marine environment, the ILC’s work codifies a more operational set of legal. The final articles were adopted in 2001 and codified additional obligations like those regarding environmental impact assessment, notification, consultation, monitoring, prevention and control of activities. These articles draw heavily from principles in previous instruments as well as the existing regime for the regulation of the marine environment. (Boyle, 2002)
- The Precautionary principle in Transboundary International Law
One of the most significant and increasingly relevant developments in international environmental law is the precautionary principle. Codified as Principle 15 of the 1992 Rio Declaration, this principle calls on states to take anticipatory action to prevent environmental degradation even when there is no complete scientific certainty .This formulation has been widely endorsed by states and provides both normative and practical guidance in shaping environmental obligations.
Further support for this principle appears in Article 3 of the United Nations Framework Convention on Climate Change (UNFCCC) which establishes that “parties should take precautionary measures to anticipate, prevent, or minimize the causes of climate change and mitigate its adverse effects.” It continues by affirming that a lack of full scientific certainty should not be used as a reason for postponing measures to prevent serious or irreversible damage. For instance, after the 2011 Fukushima Daiichi nuclear disaster in Japan, people lost confidence in the security of nuclear power plants and as a response to public outcry authorities decided to close most Japanese facilities. This decision prevented severe damage to the environment and public health. As a result of closing down the power plants, Japan had to meet its requirements with the help of fossil fuels, which further led to commercial expenses as well as heavily contributed to high levels of greenhouse gas emission further impacting climate change. The United nations Environment Programme (UNEP) Guidelines also specify that in cases where the utilization of shared resources may significantly affect the environment of another State sharing the resource, the State should make an environmental assessment. (ravichandran, n.d.) (United Nations Environment Programme, 1981) .This evolving legal consciousness is bolstered by the idea that biodiversity is a “common concern of humankind”. (Shelton, 2009) In other words, all people, regardless of nationality- have a vested interest in preserving ecosystems and preventing environmental damage, even when the impacts are not immediately felt in their own territories.
Understanding State responsibility and Liability
In international law, accountability serves as a comprehensive term encompassing both state responsibility which arises from internationally wrongful acts and state liability which includes compensation for harm resulting from lawful but damaging activities. As articulated by James Crawford, state responsibility is premised on the commission of an internationally wrongful act that can be attributed to a state (Crawford, 2013) Such a wrongful act typically involves the breach of a binding obligation under treaty law (e.g., environmental agreements) or customary international norms, such as the prohibition of environmental harm (Voigt, 2021) In the context of transboundary environmental harm, this framework becomes especially relevant. Activities within one state’s authority, whether lawful or not, may result in significant harm to another state’s environment or to areas beyond national authority. Environmental law evolves, the imperative to define, attribute, and redress such cross-border damage has brought attention to both the strengths and limitations of existing legal mechanisms. An in-depth study of all the statutory frameworks is essential in forming a prudent remark.
- UNCLOS and Marine Environmental Responsibility
The United Nations Convention on the Law of the Sea (UNCLOS) provides one of the most concrete and crystalline treaty-based recognitions of state responsibility for environmental protection. Article 235 mandates that states must fulfill their international duties to protect the marine environment and ensure that those affected by pollution caused by private actors have access to legal remedies such as compensation. (Nations, 1982) In practical application, UNCLOS falls short in handling transboundary environmental harm as its restricted to only marine pollution, there seems to be an absence of procedural enforcement mechanism or clearly defined liability threshold. For example, coral bleaching caused by global greenhouse gas emissions lacks a direct, traceable source, making legal attribution difficult. Thus, while UNCLOS acknowledges responsibility and promotes international cooperation, it does not effectively operationalize liability for environmental degradation that transcends borders.
- The ILC Draft Articles: Prevention of Harm, Not Redress
The International Law Commission’s (ILC) 2001 Draft Articles on the Prevention of Transboundary Harm from Hazardous Activities implies a pivotal step in addressing risks before they materialize. These articles aim to regulate high- and low-probability activities that may cause serious transboundary harm, placing emphasis on the preventive obligations of states rather than punitive consequences. The ILC Draft Articles avoid mandatory cessation and instead encourage a due diligence approach. This reflects a growing shift in international law towards strict liability, whereby states may bear responsibility for failing to prevent foreseeable harm, even from legal activities. However, the Draft Articles remain non-binding, limiting their capacity to ensure compliance or offer victims meaningful recourse in transboundary harm cases.
- Convention on Biological Diversity (CBD): Aspirations without Accountability
The Convention on Biological Diversity (CBD) plays an impactful role as it affirms states’ duties to conserve biodiversity (Article 1) and to prevent environmental damage that may extend beyond national borders (Article 3). Legal scholars like Catherine Tinker have argued that these provisions provide a foundation for extending state responsibility to extraterritorial environmental harm. Yet, despite biodiversity being recognized as a “common concern of humankind,” the CBD lacks any provision for liability or redress. This creates a troubling accountability gap in cases of transboundary biodiversity loss.
Systemic Gaps in Liability Frameworks
There are many systematic loopholes prevalent in establishing a lack of diligence on part of another state. As states differ widely in their capacities to protect the environment and to avoid international environmental harm, the definition of a reasonable standard of conduct is difficult to establish.
The primary challenge is, in many cases, the transboundary harm is not caused by state activity per se, but mostly by acts or omissions of private actors. In order to establish state responsibility, such acts or omissions need to be attributable to the state, or the state must have violated the obligation to apply reasonable care in its exercise of government functions (due diligence). The foundational obligation to avoid significant transboundary harm is not strict and absolute but requires that adequate and appropriate efforts are made to prevent harm. Thus, there remains an ambiguity in formalizing standard conduct of harm. (Brunnee, 2004) The second challenge is that the activities that give rise to harm are often lawful, at least in the state of origin, and may even be considered beneficial to (parts of) society. As a total prohibition seems rarely feasible, the question turns then to allowable thresholds and appropriate standards of conduct, which are often difficult to define. (Bodansky, 2010). Most transnational environmental disputes are resolved through negotiation or adoption of an agreement that regulates the issue at hand. Obligations contained in those MEAs are owed inter se to the Parties to the agreement. In some circumstances it is unclear to what extent states are entitled to invoke the responsibility of another state when it violates obligations that are owed erga omnes within a group of states (erga omnes partes) (Peel, 2001). It may thus be difficult to identify an injured state, particularly if the environmental damage is dispersed, global and/or felt in areas beyond national jurisdiction (“global commons”). (Hanquin, 2003)
To add on, unlike property damage, environmental harm has a long-lasting impact, diffuse and cumulative effect on ecosystems, biodiversity and human livelihoods. The best instance for this shall be The Corfu Chanel case, where heinous injuries and casualties occurred due to unexpected encounter with the naval mines in territorial waters of Albania. Quantifying such harm requires scientific precision, but even scientific models often carry a degree of uncertainty, particularly in attributing specific damage to a single actor in transboundary contexts. Thus, determining environmental damage, how much ought to be compensated, and how the amount of compensation is to be calculated, raises complicated economic, political, and philosophical questions. (Boyle, 2002). A core issue in addressing transboundary environmental harm is that many environmentally damaging activities such as emissions or industrial runoff—are not explicitly illegal under international law. Since state responsibility traditionally arises from wrongful acts, this limits accountability. Lastly, proving causation can be a challenge as environmental harm is often caused by the complex interplay of numerous factors, a single event, but more often by the accumulated impacts of different actions (often by different actors, and over a long time). In addition, those affected by environmental harm can range from single individual to particular groups, single states, whole regions or the community of states.
Solutions & Reflections towards mitigating this Gap.
The rising global concern over transboundary environmental harm has led to notable developments in international legal frameworks and institutional responses.
• Increasing Dependence on Soft Law Tools– Like the Rio Declaration, UNEP Guidelines, and the Draft Articles of the International Law Commission on the Prevention of Transboundary Harm. While not legally enforceable, these guidelines have influenced state conduct by advocating normative standards, such as precautionary principle and environmental impact assessments, which inform states in averting environmental harm.
• Regional and bilateral arrangements– Tools such as the EU Water Framework Directive, the ASEAN Agreement on Transboundary Haze Pollution, and the environmental protocols of the Arctic Council provide vehicles for collective monitoring, the exchange of data, and coordinated action in the face of environmental challenges. These agreements illustrate the way in which regional cooperation can produce pragmatic and actionable solutions specific to local contexts.
• Advances in technology– Environmental Impact Assessments (EIAs), remote sensing, GIS, and predictive modeling are some of the tools that have enormously enhanced the capacity of states to predict and prevent environmental damage. Technology improve warning capacities at an early stage and enhances regulatory structures in environmentally sensitive regions.
• Non-state participatory actors– Such as NGOs, Indigenous peoples, and youth movements—have emerged as strong voices through climate lawsuits, environmental diplomacy, and public mobilization. Courts all across the globe are increasingly accepting environmental rights as human rights, expanding the foundation of environmental justice.
• Multilateral Diplomacy-Spearheaded by small island developing states (SIDS) and climate-vulnerable countries, is transforming the international environmental agenda. Demands for loss and damage compensation, enhanced liability regimes, and increased climate finance signal a move toward a more inclusive and equitable policy.
Conclusion
It is obvious that the degree of sovereignty that a State has over its resources is complex. It is important to consider the foundational principles and legal precedents when exploring international environmental law. Strict application and update in old traditional frameworks is an essential component of ensuring legal adaptability, institutional relevance and the effective realization of contemporary rights and obligations.
Author- Priyanka Pillay
2nd Year student at Symbiosis Law School Pune
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