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PUBLIC INTERNATIONAL LAW: An Introduction to London (Firms)

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Public International Law 

Public international law (PIL) covers relations between States in all their myriad forms and the laws which govern State conduct, as well as regarding international organisations. Of particular salience to private legal practice are areas of PIL that have direct application for non-State actors such as multinationals, investors and individuals – including international investment law, international environmental law, sanctions and international human rights matters. In the United Kingdom, there has been a steady growth of work in the many areas of practice which fall within the broad practice area of PIL, with some practice areas seeing exponential growth over the past few years.

Arguably, the practice area falling within the more general PIL area which has seen the greatest growth in private practice in recent years is investment treaty arbitration. Investment treaty arbitration is a dispute resolution mechanism through which a foreign investor may bring claims against a State for alleged breaches of investment protections which are typically contained in a bilateral or multilateral treaty pursuant to an arbitration offer in the treaty. The International Centre for the Settlement of Investment Disputes (ICSID), one of the main arbitral institutions administering such cases, has published statistics showing 463 investment cases registered from 2010 to June 2020, almost doubling the number of cases (236) registered in the previous decade (although this also includes ICSID cases brought under contracts or national legislation). The figures show a significant growth and increased awareness of arbitration for investors against States, most usually based on PIL standards of protection and treaty frameworks.

On the investors' side, international investors (both companies and individuals) are becoming more alive to the international investment law framework and increasingly seeking advice to structure investments in order to benefit from investment treaty protections. The available statistics suggest that UK investors are taking advantage of these treaty protections, having initiated 78 ICSID arbitration proceedings between ICSID's inception and the present day. The recognition and growth in the availability of third-party funding is also allowing investors to obtain the necessary financial resources to pursue international arbitrations and other claims against States and State entities, such as in court litigation.

For States, there is also a corresponding awareness of the advantages of engaging professional external legal counsel specialised in investment treaty arbitration to assist in representing the State when faced with investment treaty claims.

International sanctions work has also seen a marked increase in recent years. This concerns sanctions at the United Nations, United States and European Union levels. Concerning the latter, the UK's withdrawal from the EU has necessitated further legislation concerning sanctions and anti-money laundering, adding another legal layer to the applicable legislation and regulation in this area. Following the expiration of the transition period at the end of 2020, the UK's sanctions regime will be unmoored from the EU and the UK will be in a position, subject to international obligations, to set its own sanctions regime. It is not surprising that sanctions developments have prompted increased advisory and litigation engagements – not just to ensure applicable sanctions are complied with, but also to challenge the imposition of sanctions before UN bodies as well as at the EU and UK levels.

Trade law has also seen a significant increase in work, some of which has also been related to the UK's withdrawal from the EU, including because of the (current) lack of agreement as to how and under what conditions or constraints the UK will have access to the single market.

Another notable area of increased work concerns international human rights law and constitutional litigation, including issues concerning business and human rights. Matters in this area are increasingly diverse, ranging from proceedings before the International Court of Justice (such as the proceedings initiated by Qatar against the United Arab Emirates under the Convention on the Elimination of All Forms of Racial Discrimination) to cases before the UK Supreme Court (such as the case of Vedanta Resources Plc and Konkola Copper Mines Plc (Appellants) v Lungowe and Ors. (Respondents) [2019] UKSC 20, which concerns the responsibility of a UK company for alleged violations of obligations arising from business and human rights).

In other areas of PIL practice, States are increasingly requesting support from private legal practice on issues related to international humanitarian law, international criminal law, the law of the sea and issues of State sovereignty and territory, including territorial and boundary disputes. Matters of State immunity remain a mainstay of PIL legal practice, particularly (but by no means exclusively) where they overlap with issues of enforcement in the courts. International institutional law is another area that has witnessed growth in private practice, sometimes combined with issues of immunity.

Finally, a topic which will continue to receive more attention in the coming years relates to climate change. PIL practices have increasingly been considering the long-term legal implications of climate change, including in conjunction with law of the sea issues. For example, the ice-melt in the Arctic and the consequent sea-level rise has become the object of international discussions and calls for further legal development. We anticipate increased litigation in this area before international and national courts in the foreseeable future.

In conclusion, the area of PIL is experiencing remarkable growth in the UK, encompassing increasingly varied areas of practice, as international actors are faced with increasingly complex and novel social, political, technological and environmental issues requiring the application of international law. This has led to significant interest from the relevant actors on strategies to better access and protect rights granted under international law, not only through advisory work but also through dispute resolution proceedings.

Hussein Haeri, Robert Kovacs, Clàudia Baró Huelmo – Withers LLP