PhD (Fitzwilliam College, University of Cambridge)
LL.M. (University College London)
Diplom-Jurist (University of Bayreuth)

Stefan is a Postdoctoral Research Fellow at the Bonavero Institute of Human Rights. His primary research interests are in public law, human rights, and constitutional law. Born in Bangkok and raised in six countries on four contintents, Stefan completed his first degree in law at the University of Bayreuth (2011). After brief stints working for a commercial law firm and for the Research Services of the German Bundestag, Stefan earned an LL.M. from University College London (2013). Inspired to pursue a career in academia, he completed his doctoral work at the University of Cambridge (2018) shortly before joining the Bonavero Institute as the Postdoctoral Research Fellow in Civil and Political Rights.

You can follow Stefan on twitter and discover his papers on SSRN and ResearchGate.


Stefan's research agenda is still evolving and specialising. In his PhD dissertation he argues for the recognition of a comprehensive framework that addresses the relationship between human rights and environmental harm: the environmental minimum. The argument is based on a unique and comprehensive dataset of the case law of the European Court of Human Rights, along with other regional human rights courts. He is contracted to develop a revised version into a monograph (Cambridge University Press, expected 2021).

Stefan is the academic lead for the Bonavero research project Freedom of expression on social media. The core research question is whether the environment of social media requires the law to revisit some of the principles and assumptions underlying conventional offline approaches to freedom of expression. This relates chiefly to the scope for legitimate suppression of hate speech as well as the limits that free expression imposes on the contractual autonomy of social media platforms with their users.

Beyond human rights, Stefan is generally interested in public and constitutional law, particularly as it operates in the United Kingdom, Germany and the European Union. He leads the research project Prorogation of Parliament and has appeared on BBC News television and various BBC Radio outlets outlets to offer legal commentary on the proceedings before the UK Supreme Court. He writes and blogs frequently on legal developments, often drawing comparisons between legal systems and reflecting on deepening European integration.


Stefan teaches on the Human Rights Law course, which is offered as an option on the FHS and the BCL course Constiutional Principles of the EU. The content of the lectures and seminars continues to evolve with recent legal developments, most notably the constitutional shifts due to Brexit. 


Displaying 1 - 29 of 29. Sorted by year, then title.
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  • S Theil, 'Unconstitutional prorogation of Parliament' [2020] Public Law 529
    Argues, contrary to the constitutional convention, that the monarch is empowered in certain situations to reject ministerial advice to prorogue Parliament. Reviews evidence for the convention on prorogation, including statutory powers and ministerial advice, and considers the constitutional implications. Examines criticisms of R. (on the application of Miller) v Prime Minister (SC), and potential remedies open to the monarch for executive abuses.
  • S Theil, 'Germany – a federal executive power grab?' (2020) UK Administrative Justice Blog
    The German Infectious Diseases Protection Act (Infektionsschutzgesetz – IDPA) is the primary federal statute regulating the fight against covid-19 in Germany. The Act has been recently amended to provide the federal government with a greater role in enforcement and expanded its authority to pass delegated legislation without the consent of the Bundesrat. The Bundesrat is representative body of the German states at the federal level whose consent is ordinarily required before any law can be enacted or amended that impacts on the state sphere of competence. This post provides an overview of the IDPA framework and highlight some initial preliminary rulings from German courts, most notably from the Constitutional Court, before turning to assessing the constitutionality of the newfound powers of the federal executive.
  • S Theil, 'Loremza Violini and Antonia Baraggia (eds.) The Fragmented Landscape of Fundamental Rights Protection in Europe – The Role of Judicial and Non-Judicial Actors (Edward Elgar, 2018)' (2020) Modern Law Review [Review]
    DOI: 10.1111/1468-2230.12500
    Lorenza Violini and Antonia Baraggia are the editors of a recent collection entitled The Fragmented landscape of fundamental rights protection in Europe – The role of judicial and non-judicial actors. The book has taken on a broad and ambitious topic in the notoriously complex and interdependent environment that is the European legal architecture, particularly in terms of relevant actors. The chapters are arranged along three broad themes: (a) the theoretical complexity of fundamental rights protection, (b) the role of courts and (c) the various roles of non-judicial actors. The book contains some outstanding contributions and generally offers thoughtful reflections on at times under researched subjects. A core challenge to overcome with such a broad topic is that it can be difficult to identify overarching themes and tease out deeper insights, thus offering readers something beyond the sum of the contributions. Unfortunately, the present collection has not been successful in this respect. The chapters stand primarily on their own terms and rarely offer insights beyond their at times narrow topics. Reflections on other chapters are rare, even where they seem to strongly suggest themselves and express engagement with the overarching topic of the book is largely absent, barring a few exceptions. The laudable mission of the book to ‘address the flaws and the challenging overlaps fostered by the fragmented and complex landscape of fundamental rights protection in Europe from a novel perspective’ (1) is thus not quite achieved.
  • S Theil, 'Germany - Federal Constitutional Court on the horizontal effect of equality rights between private parties' [2020] Public Law 181 [Case Note]
    On 27 August 2019 the German Federal Constitutional Court (FCC) rejected the application of a prominent German far-right politician alleging discrimination by a privately-owned wellness hotel. The hotel had initially confirmed the politician’s four day reservation, but then cancelled and directed the applicant to alternative accommodations in the area. Upon receiving a request for clarification the hotel banned him from entering the premises indefinitely, explaining that his vocal far-right political beliefs would inconvenience other patrons and damage the reputation of the establishment. The applicant challenged the decision before the FCC, claiming that the court’s finding that the hotel could exclude the applicant from future bookings amounted to a violation of his constitutional equality rights. The FCC found that the applicant’s desire to stay in a particular hotel was not significant to his societal participation and that the hotel was far from the only establishment in the resort town in question. Hence, it concluded there was no violation of constitutional equality rights in this case.
  • S Theil, 'Excavating Landmarks—Empirical Contributions to Doctrinal Analysis' (2019) Journal of Environmental Law
    The idea of landmark cases is ubiquitous in legal scholarship and adjudication. Both scholars who rely on ‘landmark’ cases and those who avoid the label often focus too much attention on a small sample of individual cases when researching legal doctrine. This risks missing important cases and pieces of the doctrinal picture. The article proposes an updated methodology that returns ‘to the basics’ of doctrinal scholarship, but with an empirical twist enabled through modern database technology. The approach is exemplified through the case study of López Ostra v Spain, a well-known environmental human rights decision under the European Convention on Human Rights. Based on a comprehensive data set of all environmental decisions, the article argues that the ‘landmark’ status of López Ostra is less empirically and doctrinally clear than conventionally accepted in legal scholarship.
  • S Theil, 'The Problem with the Normative Content of Section 24 of the Constitution of South Africa' (2019) 37 Nordic Journal of Human Rights 105
    DOI: 10.1080/18918131.2019.1643669
    The article critically examines the South African Constitutional Court (ZACC) case law and doctrine on section 24 (right to an environment) of the Constitution of South Africa. It argues that the right has been left normatively impoverished, and especially the interaction and relationship with the cornerstone statute, the National Environmental Management Act (NEMA) remains unclear. This issue centres specifically around three core issues. First, it has not been settled whether section 24 encompasses an individual right and an additional positive obligation, or constitutes a composite right. Second, the individual right contained in section 24 requires further definition and clarification. Key terms have not been given distinctive constitutional contours, and it remains uncertain to what extent legislative instruments such as NEMA are legitimately filling these gaps. Finally, it is unclear how the principle of constitutional subsidiarity applies to section 24 of the Constitution. Even assuming that the principle applies in essentially the same way as to other constitutional provisions, one cannot reasonably determine whether ordinary legislation reflects and gives effect to a constitutional right, if one has no clear notion of the latter’s content.
  • S Theil, 'The Online Harms White Paper: Comparing the UK and German Approaches to Regulation' (2019) Journal of Media Law 1
    DOI: 10.1080/17577632.2019.1666476
    The internet has revolutionised our ability to communicate and connect across historic social, political and geographic divides. Where previously gatekeepers mitigated and negotiated access to mass media platforms, today potentially anyone – and any content – can reach millions of users in an instant. This development bears great opportunities for the democratisation of expression and the diversification of public discourse but has likewise broadened the impact of harm caused online. This raises the question how platforms and services can be regulated effectively to combat online harms without jeopardising free and open discourse. The paper explores the Online Harms White Paper published by the UK Government earlier this year and compares its regulatory approach with the infamous German Network Enforcement Law.
  • S Theil, 'Germany - Federal Constitutional Court qualifies the distinction between fundamental rights obligations of the state and private actors' [2019] Public Law 790 [Case Note]
    The German Federal Constitutional Court (FCC) recently issued a significant decision requiring Facebook to reinstate the page of a far-right party in the lead up to the European Parliament election. The party had shared content to its page which Facebook classified as violating provisions of its community standards on hate speech. Facebook first curtailed the visibility of the posts and prevented the sharing of further content, before ultimately deleting the page entirely. The case suggests that at least where private actors have acquired a level of market dominance and provide a significant platform for public communication and discourse, freedom of expression can legitimately limit their contractual autonomy: perhaps to the point where the obligations are indistinguishable in practice from those of the state.
  • S Theil, 'Prorogued until October? How the Prorogation Act 1867 could be used to sideline Parliament for good' (2019) Verfassungsblog
    The British government under Prime Minister Boris Johnson yesterday secured a prorogation of Parliament from the Queen. Barring an intervention from the courts, Parliament will stand prorogued no earlier than Monday 9th September and no later than Thursday 12th September 2019 to Monday 14th October 2019. Much attention focused on the timing of the prorogation. The government evidently sought to avoid the impression that the sole, or indeed primary goal of the prorogation was to cut short the time for parliamentary debate of Brexit. For many commentators the weeks from now until 12 September and from 14 October to 31 October (the day the United Kingdom exits the European Union) were crucial. It tipped the balance of the prorogation from blindingly unconstitutional to constitutionally dubious, but permissible. Regardless of whether one finds this line of reasoning convincing, there is a threat that this prorogation can be extended indefinitely that has been largely overlooked: the Prorogation Act 1867.
  • S Theil, Jacob Rowbottom, Catherine O’Regan and Oliver Butler, Response to the public consultation on the Online Harms White Paper (Bonavero Report 3/2019, Bonavero Institute of Human Rights 2019)
    This constitutes the joint response of Oliver Butler, Kate Jones, Harriet Moynihan (Chatham House), Catherine O’Regan, Jacob Rowbottom and Stefan Theil to the public consultation on the Online Harms White Paper. Our overarching recommendation is that any regulatory approach to online harms should be expressly founded on human rights law. Human rights law provides both a suitable normative framework as well as crucial guidelines to assist regulatory decision-making, especially in balancing competing rights and interests in the online sphere. While the White Paper frames its approach as involving a duty of care, we believe that this terminology may be misleading: the codes of practice and the penalties for transgressions are better understood as conventional instruments of statutory regulation. We have rule of law concerns due to the broad scope of platforms and services covered. The regulator must be able to provide meaningful oversight and companies require clarity on what enforcement measures they can expect. Comparable legislation, like the Network Enforcement Law in Germany, is limited to larger companies and focused on a narrower set of platforms and services. If the broad scope outlined in the White Paper is retained, we suggest the regulator considers exempting certain companies partially or entirely from regulation (see Question 5). Legislation should consider a two-tier approach to regulation which differentiates between: (a) harms with a strong evidence basis and a reasonably clear definition (‘definite harms’) and (b) harms with a weaker evidence basis or with a less clear and context-specific definition (‘contextual harms’). While a prescriptive regulatory approach to definite harms seems appropriate, legislation may provide a more flexible oversight model for contextual harms. This would permit a degree of variation as to the standards applied by companies, increasing the choices available to users (see Question 8).
  • S Theil, 'Nadine Strossen, Hate: Why We Should Resist It with Free Speech, Not Censorship (Oxford University Press 2018)' (2019) 69 University of Toronto Law Journal 404 [Review]
    Across nine chapters, Strossen draws on some evidence from social sciences and psychology as well as comparative legal perspectives to defend the orthodox approach of the Supreme Court to free speech. At the heart of the book stands an optimistic and at times idealistic belief in the individual, especially their capability to challenge and mitigate the harms associated with hate speech. This optimism is admirable, even when it appears at odds with historic and contemporary treatment of marginalized groups. Despite its many merits and thoughtful contributions, there are also some significant points of criticism that relate chiefly to the comparative legal work and deficits in scholarly rigor. Strossen plainly has a strong view in the normative debate on free expression, but her superficial exercise in comparative human rights does the argument no favours: it reduces the examined legal systems to crude caricatures. The book thus illustrates the challenges faced by scholars engaged in comparative work. Apart from detailed and careful research, they must adopt a strong methodology that counteracts tendencies to cherry pick examples that support foregone conclusions.
  • S Theil and K O'Regan, Comments on Facebook’s draft Charter for an independent review board (Bonavero Report 2/2019, Bonavero Institute of Human Rights 2019)
    Facebook has invited comments from experts and civil society on its draft charter ‘An oversight Board for Content Decisions’. The Bonavero Report focuses in turn on three major areas of debate: (1) the mission of the independent board what issues it can and should address and practical concerns relating to the competing models; (2) the standards of review the independent board ought to apply in fulfilling its mission,and the corresponding implications for Facebook and its content moderation system;and finally (3) the institutional design of the independent board, how it will secure its independence, determine its membership, and the procedures employed.
  • S Theil, 'Unconstitutional Prorogation' (2019) UK Constitutional Law Blog
    The piece develops a twofold argument: first, that ministerial advice tendered to seek a prorogation of Parliament under these circumstances is unconstitutional and that the Monarch should disregard it as a matter of constitutional convention; and second that holding otherwise would in effect grant the Prime Minister an unqualified veto over parliamentary business, leaving the government in an unconscionable position of power over the sovereign Parliament. Such an outcome would be fundamentally at odds with British parliamentary democracy, especially principles of democracy and representative and responsible government.
  • S Theil, 'The German NetzDG: A Risk Worth Taking?' (2018) Verfassungsblog
    This contribution gives a succinct overview of the NetzDG and explain how some of the criticisms are overstated and partially misguided. While the NetzDG is unlikely to resolve all challenges surrounding social media and freedom of expression, and undoubtedly presents a certain risk of stifling expression online, I believe it is nonetheless a significant step in the right direction. Rather than undermine freedom of expression, it promises to contribute to more inclusive debates by giving the loud and radical voices less prominence.
  • S Theil, 'Preambles in the text and context of constitutions' in Markus Kotzur (ed), Peter Häberle on Constitutional Theory - Constitution as Culture and the Open Society of Constitutional Interpreters (Hart Publishing / Nomos 2018)
    DOI: 10.5771/9783845289519-257
    Translation from German, originally published in 1979 as 'Präambeln im Text und Kontext von Verfassungen'
  • S Theil, 'The rationale of constitutions from a cultural science viewpoint' in Markus Kotzur (ed), Peter Häberle on Constitutional Theory - Constitution as Culture and the Open Society of Constitutional Interpreters (Hart Publishing / Nomos 2018)
    DOI: 10.5771/9783845289519-229
    Translation from German, originally published in 2006 as 'Der Sinn von Verfassungen in kulturwissenschaftlicher Sicht'
    ISBN: 9781509926299
  • S Theil, 'An Aversion to Weimar: German Constitutional Hesitance on Dissolving the Bundestag' (2017) UK Constitutional Law Blog
    Now that the next German government is unlikely to be formed, Germany is left with two equally unattractive options: a minority government under CDU/CSU leadership or fresh elections following dissolution of the Bundestag. The procedure for both is complicated under the German constitution, and this post will seek to shed some light on the constitutional hurdles. There are broadly speaking two scenarios in which the Bundestag may be dissolved and fresh elections sought, as well as a minority government formed.
  • S Theil, 'Is the ‘living instrument’ approach of the European Court of Human Rights compatible with the ECHR and International Law?' (2017) 23 European Public Law 587
    The article offers a rebuttal of prominent criticisms directed against the ‘living instrument’ interpretative approach of the European Court of Human Rights. The article initially introduces the basic application of the interpretative approach as adopted by the Court and then considers whether it is compatible with the Convention and broader International Law. The article argues that the Preamble, subsequent State practice and preparatory work offer inconclusive evidence to both critics and supporters of the ‘living instrument’. However, the interpretative approach can claim democratic endorsement through States, while arguments based on the necessity to consider domestic interpretations of the European Convention on Human Rights (ECHR) cannot support a restrictive interpretation as a matter of International Law. The ‘living instrument’ further appears compatible in the context of state sovereignty in International Law, and broader institutional concerns with the role of judges in the adjudication of rights. Ultimately, the ‘living instrument’ interpretative approach therefore appears legal under the Convention and relevant International Law.
    ISBN: 1354-3725
  • S Theil, 'A vote of confidence for the German democratic order: the German Federal Constitutional Court ruling on the application to ban the National Democratic Party' (2017) U.K. Constitutional Law Blog
    On 17 January 2017, the German Federal Constitutional Court (FCC) ruled on the application of the German Federal Council to find that the far right National Democratic Party of Germany (NPD) unconstitutional pursuant to Article 21 para. 2 of the German Basic Law. This constituted the second such party ban application against the NPD after the initial attempt in 2001 had failed on procedural grounds, chiefly due to the involvement of domestic intelligence agency informants in the higher echelons of the party. Having been assured that these informants were no longer operating, the most recent application passed the admissibility hurdle, but was ultimately not successful on the substance: the FCC found that while the NPD was clearly determined to undermine and abolish key features of the free democratic basic order of Germany, its actions had such little prospect of success that it could not be deemed unconstitutional.
  • S Theil, 'Neither full independence, nor perfect union: Constitutionalism as a Third Way for the future of Scotland' (2017) LSE British Politics and Policy Blog
    With Scotland now to seek a second independence referendum, the debate is framed around two extreme options: independence or union. Stefan Theil writes that a third option is available if both sides are prepared to make concessions. He explains how constitutionalism, paired with a federal settlement, could come to offer a viable long-term solution for Scotland.
  • S Theil, 'Introducing the Environmental Minimum' (2016) University of Cambridge Faculty of Law Research Paper
    This paper will present the core argument in favour of establishing the environmental minimum as a framework for the relationship between the protection of the environment and human rights. In simplified terms, the environmental minimum seeks to protect those basic environmental conditions that are necessary for the meaningful enjoyment of human rights, chiefly by providing a framework that fosters an active engagement with environmental degradation, its regulation and enforcement.
  • S Theil, 'A union of states, constitutions, administrations and judiciaries: some initial thoughts on the OMT ruling of the German Constitutional Court' (2016) U.K. Constitutional Law Blog
    In the midst of the all-consuming Brexit Referendum Debate, and the unfortunate vote by the United Kingdom to Leave the EU, one might be forgiven for having overlooked this particular piece of European integration litigation. If nothing else, this recent decision by the German Federal Constitutional Court (FCC) demonstrates that even in a difficult constitutional relationship, the spirit of cooperation and pragmatism can triumph over ideological differences. In that sense, the FCC has long been a sturdy pillar in the European constitutional order, one that the remaining member states and the EU can rely on for stability in the uncertain months and years that are sure to follow the invocation of Article 50 TEU.
  • S Theil, 'Constitutions as culture: Two insights from Peter Häberle’s “The rationale of constitutions from a cultural science viewpoint"' (2015) U.K. Constitutional Law Blog
    Constitutions are the cultural achievement of centuries of historical legal development, an expression of the cultural self-presentation of a people. For all their variety, constitutions seek to set the rules for a fundamental order in an objective, rational and principled manner. The general structure of the state, the inclusion and contours given to basic legal principles (Rule of Law, Separation of Powers, Legality) and the human rights a society may wish to uphold receive varied and diverging replies in the Constitutions analysed by the Constitute Project. From the very beginning of the drafting process, those replies can scarcely be separated from the cultural background on which the views and perspectives on these matters of principle are based.
  • S Theil, 'Polycentricity – A fatal objection to the adjudication of environmental rights?' (2015) U.K. Constitutional Law Blog
    In an unprecedented ruling, the Hague District Court has recently compelled the Dutch State to reduce the greenhouse gas emissions of the Netherlands by 25% by 2020 based on the emissions levels of 1990. The Urgenda Foundation had successfully argued that the Dutch State was under an obligation to protect its citizens form climate change on the basis of domestic tort law. For many this development is symptomatic of a broader, more general concern: a court engaging with a highly complex policy question, which is better left to other modes of decision-making. Lon Fuller makes the strongest and most fully developed argument along this view in his article on polycentricity. Although Fuller does not reference environmental protection specifically, his concerns are readily transferable: if threshold values for dangerous air pollutants are exceeded, regulators may resolve the matter through a vast number measures ranging from limiting vehicular traffic to long term shifts towards cleaner energy production. In essence, Fuller argues that choosing between these options or indeed setting binding targets with any nuance is a task ill-suited to courts.
  • S Theil, 'Three insights from Peter Häberle’s “Preambles in the text and context of constitutions"' (2015) U.K. Constitutional Law Blog
    Preambles are a hallmark of constitutions, and questions regarding their inclusion and content are an important part of the drafting process: a clear majority of the 194 constitutions analysed by the Constitute Project opted in favour of more or less expansive preambles. In this country, an early draft of a Constitution for the UK by the Institute for Public Policy Research included a preamble, and a more recent effort of the Institute of Public Affairs at LSE at crowdsourcing a UK Constitution will likely address the question in due course. Certainly, we would not deem a preamble an absolute necessity. There is a sizeable minority of written Constitutions without preambles. Most recently in the UK, the draft Scottish Independence Bill (2014), whose Part 2 was intended to serve as an interim constitution in the event of independence, contained no preamble. In spite of the mixed evidence on the necessity preambles, we may well have good reasons to incorporate them into constitutions: preambles express aspirations, hopes and commitments to higher ideals in a particularly exalted language. As Peter Häberle surmised, they thus attempt to foster a link to the history and culture of a nation, provide a justification and rationalization for the birth of the constitution, and establish a connection with its citizens, while also influencing the interpretation and application of the law.
  • S Theil, 'What red lines, if any, do the Lisbon Judgments of European Constitutional Courts draw for future EU integration?' (2014) 15 German Law Journal 599
    The paper critically examines the Lisbon decisions of European Constitutional Courts and attempts to tease out what red lines they draw for future European integration. Overall, the Constitutional Courts leave much hope for an enduring legal development of the EU. The only definitive red line is not of a legal, but of a moral nature. As long as the EU continues to exist for the sake of the European People,and the common good is truly best served by it, then deeper integration can be morally justified, politically achieved, and legally implemented. This conception of the European idea, this dream of Europe, can be defended in the face of critics, regardless of the red lines to integration.
  • S Theil, 'Der Umfang des Umweltschutzes in der Rechtsprechung des Europäischen Gerichtshofs für Menschenrechte' (2014) 36 Natur und Recht 330
    Mit dem erneuten Scheitern der jüngsten Klimakonferenz in Warschau wurde abermals die mangelhafte Umsetzung verbindlicher Klimaschutzziele durch die Politik auf internationaler Bühne demonstriert. Doch nicht nur auf Klimakonferenzen obsiegen oft nationale Interessen an Wohlstand und Wirtschaftswachstum über die langfristigen Belange des Umweltschutzes. Einige Stimmen schlagen deshalb vor, umweltrechtliche Belange als ein Problem des Menschenrechtsschutzes zu begreifen, um so dem Umweltschutz mehr Durchsetzungskraft zu verleihen. Der Beitrag untersucht anhand der Rechtsprechung des Europäischen Gerichtshofs für Menschenrechte, in wie fern der internationale Menschenrechtsschutz bereits heute Umweltbelange anerkennt und welche Grenzen diesem Bestreben gesetzt sind.
    ISBN: 1439-0515

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Research Interests

Human Rights; Public Law; Constiutional Law; European Union Law; International Law; German Law

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Human Rights Law, Constitutional Principles of the EU

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