Aerial Incident of 23 May 2021: Belarus and the Ryanair Flight 4978

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It was widely reported on Sunday that the government of Belarus forced a Ryanair flight bound for Vilnius to land in Minsk on account of a ‘potential security risk’. The flight was escorted to Minsk by Belarussian MiG-29 fighters. As the BBC put it:

Flight FR4978 was en route from Athens to the Lithuanian capital Vilnius on Sunday when it turned east to Minsk shortly before it reached the Lithuanian border. Greece and Lithuania put the number of passengers on board at 171.


The flight path, visible on the Flightradar24 website, suggests the plane was actually nearer to Vilnius than Minsk when it turned.

Ryanair said checks in Minsk found ‘nothing untoward’ and the aircraft was cleared to depart after about five hours on the ground.

The reports further state the Belarusian President Alexander Lukashenko gave the order for the plane to be diverted, and scrambled fighters to intercept and escort it to Minsk, citing a bomb threat. On board the plane was Roman Protasevich, a 26-year-old journalist who is a staunch critic of the regime in Belarus and who has been declared a terrorist by it and charged with a number of crimes under Belarusian law. Upon landing in Minsk, Protasevich was taken from the plane and detained. Condemnation by political leaders has been swift. There is much to be said about ongoing human rights violations in Belarus, including the persecution of journalists.

In this post, however, we focus on certain legal issues in relation to the diversion itself. In particular, we discuss whether states may order civil aircraft flying over their territory to land for certain purposes, eg to determine whether there are explosives on board or to detain a criminal suspect, and whether they are entitled to compel them to do so – questions that arise under the Chicago Convention. We also discuss briefly responsibility under the Montreal Convention, as well as the use of ‘hijacking’ language and The Hague Convention. We finally raise issues of invocation and implementation of state responsibility for the internationally wrongful acts potentially committed.

The Chicago Convention

The place to start is the Chicago Convention of 1944. Indeed, ICAO itself reacted on twitter:

ICAO is strongly concerned by the apparent forced landing of a Ryanair flight and its passengers, which could be in contravention of the Chicago Convention. We look forward to more information being officially confirmed by the countries and operators concerned.

There is no doubt that states have sovereignty over their airspace, as per Article 1 of the Convention and customary international law. However, in accordance with Article 3 bis (a) of the Convention, states ‘recognise’ their obligation to refrain from using weapons against civil aircraft in flight, the provision making direct reference to the obligations under the UN Charter. This is (in part) a reiteration of the prohibition of threat or use of force in Article 2(4) of the Charter (though it goes beyond that as it prohibits use of force even against civil aircraft registered in the territorial state). Under 3 bis (b), a state is entitled to require landing at a designated airport of a civil aircraft flying above its territory only when the latter is flying ‘without authority’ (which was not the case here), or ‘if there are reasonable grounds to conclude that it is being used for any purpose inconsistent with the aims of this Convention’. A bomb on board a plane may qualify as that plane being used for purposes inconsistent with the aims of the Convention, which include avoidance of ‘abuse [of civil aviation that] can become a threat to the general security’, as per the Preamble.

However, it appears that there was no bomb on the Ryanair flight, nor has Belarus provided any evidence that it had any ‘reasonable grounds to conclude’ that there was—there is so far merely an assertion. The next question is whether the presence of an alleged criminal (or terrorist) on board a flight would constitute an (ab)use of civil aviation that is inconsistent the Chicago Convention aims mentioned above. That is doubtful: if it were so, then every state could interfere with civil aircraft traversing its airspace if it had ‘reasonable grounds to conclude’ that a suspected criminal/terrorist was on board the flight, which would no doubt wreak havoc on air travel. That does not seem to us to be a plausible interpretation of the provision or of the aim of avoiding abuse of civil aviation to safeguard ‘general security’. Rather, it seems as an abuse of powers over civil aviation on the part of the territorial state.

There is no doubt that if Protasevich were driving through Belarus, his car (even a foreign-registered car) could be stopped and he could be detained, and that would be a commonplace exercise of jurisdiction. One may ask why it should not be so in the case of air travel. The reason is that airspace is not fully assimilated to land territory in terms of the exercise of sovereignty and thus jurisdiction. It is the Chicago Convention and customary law that determine the extent of state powers over airspace, much like it is the UN Convention on the Law of the Sea and customary law that determine the extent of state powers over the territorial sea. And even though there is no right of innocent passage through national airspace (as there is in the case of the territorial sea), the Chicago Convention does establish a form of right of unencumbered passage once permission to enter/traverse has been given, otherwise all civil aviation would be at the whim of each and every territorial state.

If that is so, then the Belarusian requirement that the plane divert and land at Minsk under false pretences, and indeed even more so the scrambling of fighters to intercept and escort the flight to the airport, which must constitute at least a threat of force, are in breach of Belarusian obligations under Article 3 bis of the Chicago Convention. We note that interception, in particular, will likely entail a threat of force when undertaken by fighters: the flight commander must comply with instructions of interceptors or risk action against the aircraft.

The Montreal Convention

A second legal basis upon which the international responsibility of Belarus can be established is the Montreal Convention of 1971. Article 5 of the Convention requires state parties to establish jurisdiction over certain offences against the safety of civil aviation. Article 1 of the Convention defines those offences, and includes in paragraph 1(e):

Any person commits an offence if he unlawfully and intentionally: … (e) communicates information which he knows to be false, thereby endangering the safety of an aircraft in flight.

On the face of the reports, it appears that such an offence was committed. As the BBC reported, Ryanair said that the crew was ‘notified by Belarus (Air Traffic Control) of a potential security threat on board and were instructed to divert to the nearest airport, Minsk’. On the other hand, the editor-in-chief of NEXTA, of which Protasevich was the co-founder, reported on twitter that Belarusian KGB agents on board the aircraft insisted that there was an improvised explosive device. In the instance, there is no indication that there was any risk to the plane at all, and in the light of the reports that there was an ulterior motive for the diversion, we can reasonably assume that it was the information communicated was knowingly false, and thus endangered the safety of the aircraft.  

If an offence as defined in the Convention has been committed, the next question is responsibility. We do not deal here with individual criminal responsibility, other than to note that any state organ that perpetrated the offence (eg the KGB agents on board, if they were the ones to relay the false information) will certainly enjoy at least immunity ratione materiae. In this respect, one possibility is a broad application of the reasoning in Pinochet – the assumption by state parties of a duty to establish jurisdiction over the offences in the Montreal Convention entails an implied waiver of immunity ratione materiae. One problem here, however, is that the Convention against Torture, at issue in Pinochet, is not quite analogous. In relation to CAT, it is the definition of torture as requiring state involvement that drives the argument that without waiver the relevant provisions of the Convention would be frustrated. By contrast, the Montreal Convention was adopted precisely to deal with non-state action against the safety of civil aviation. Even though state action is also conceivably captured by the Convention, it is more difficult to make the argument that waiver of immunity is necessarily implied.

As to state responsibility, Article 10(1) of the Montreal Convention provides:

Contracting States shall, in accordance with international and national law, endeavour to take all practicable measure [sic] for the purpose of preventing the offences mentioned in Article 1.

The facts, as reported, seem to be a relatively straightforward breach of Article 10(1) by Belarus – a failure to prevent the relevant offence from taking place.

In addition, there is the tricky question of whether the Montreal Convention also imposes on states an obligation not to commit the offences set out in Article 1 – an obligation that might be implied from the obligation to prevent in Article 10(1). In this respect, the decisions of the ICJ in the Bosnian Genocide case (para 166) and on Preliminary Objections in Ukraine v Russia (para 59) seem to point in different directions. Determining the better view of the position under the Montreal Convention would require further work. In any event, however, the preventive duty remains applicable.

‘State Hijacking’ and The Hague Convention

 The BBC and NYT both reported statements by Lithuania that the civilian aircraft was ‘hijacked by military force’, and by the Greek Foreign Ministry that this was a ‘state hijacking’. This language has also been used in reporting the events. However, we should note here that in accordance with the Convention for the Suppression of Unlawful Seizure of Aircraft (The Hague 1970), there is such unlawful seizure if a person on board an aircraft in flight seizes or exercises control of that aircraft (or attempts to do so) by means of threat or force or through other form of intimidation (Article 1). This is what is colloquially referred to as hijacking, and it does not appear that this happened in the instance. Even though the Guardian reports that there were Belarusian KGB agents on the flight, there is no indication that they used intimidation or threats or force in order to seize control of the aircraft. Had the agents actually seized control of the aircraft, then we could be dealing with a breach of the obligation of the state under Article 9 of The Hague Convention to ‘preserve the control’ of the lawful commander of the aircraft.

 Questions of the Invocation of Responsibility

Assuming that there is an arguable case that Belarus has breached its obligation under the Chicago and the Montreal Conventions, the question is who can invoke the state’s responsibility for the internationally wrongful acts. If Poland is the state of registration of the aircraft, then it can certainly invoke that responsibility in accordance with the rule reflected in Article 42 of the Articles on State Responsibility. Potentially so can the Republic of Ireland as the state of incorporation of Ryanair by means of diplomatic protection, once Ryanair at least attempts to exhaust any remedies available under Belarussian law.

However, and more importantly, we argue here that the relevant obligations in the Montreal Convention are actually established for the protection of collective interests of the group of states parties to the Convention. They thus constitute obligations erga omnes partes, meaning that all parties to the Convention can invoke the responsibility of Belarus in accordance with the rule reflected in Article 48(1)(a) ASR. This is not a claim we make lightly: the obligations in the Montreal Convention are multilateral obligations that can be bilateralised in any given instance. To argue that they constitute obligations erga omnes partes requires some anchoring in the text and/or the object and purpose of the Convention. We argue that this anchoring is provided by the ‘extradite-or-prosecute’ obligation in Article 7 of the Convention. This obligation, noted as being applicable ‘without exception whatsoever’, aims to cast a net over all state parties to the Convention in order to secure its implementation. This must be taken to signify that the obligations in the Convention are not merely owed to individual state parties through bilateralisation, but are also owed to all states-parties as they have been established for the protection of a collective interest of the group, namely the protection of safety of civil aviation. As such, any one of the other 187 state parties to the Montreal Convention can invoke Belarusian responsibility for the breach, and demand that it comply with its secondary obligations to cease the breach if it is continuing (it is, as long as the relevant offenders are not prosecuted), to offer assurances and guarantees of non-repetition (eg through adoption or amendment of relevant domestic legislation), and to offer reparation to the directly injured state (eg Poland and/or the Republic of Ireland).

Assuming that Belarus rejects the invocation of its responsibility along the lines described above, this would give rise to a dispute between the state invoking Belarusian responsibility and Belarus under the Montreal Convention. Article 14(1) of the Convention provides for any dispute as to the interpretation or application of the Convention that cannot be settled by negotiation to be submitted to arbitration at the request of any of the parties and, if such arbitration cannot be organised by agreement of the parties within six months, to be referred to the ICJ by any of the parties. However, Belarus has declared that it does not consider itself bound by this provision, as it is explicitly entitled to do under Article 14(2).

This does not mean that the state(s) invoking Belarussian responsibility cannot determine for themselves and at their own risk that Belarus has not only become responsible for a breach of the Convention, but has also failed to comply with its secondary obligation, and thus resort to countermeasures—a matter which is taken up in the next section.

Before turning to that, however, it is worth mentioning that recourse to international adjudication may not be fully precluded in the instance. Invocation of responsibility under the Chicago Convention would follow similar lines as the ones under the Montreal Convention. The obligations under Article 3 bis, being as they are but an implementation of the prohibition of the threat or use of force under the UN Charter and customary law, must be seen again as an obligation owed erga omnes partes, entitling any of the other 190 state parties to the Chicago Convention to invoke the responsibility of Belarus. As per Article 84 of the Chicago Convention, any ‘disagreement’ (which the ICJ has interpreted as ‘dispute’, and which indeed is referred to as dispute later in that provision and in Article 85) as to the interpretation or application of the Convention that cannot be settled by negotiation shall be decided by the ICAO Council ‘on the application of any state concerned in the disagreement’. Any decision of the ICAO Council (including, as per the jurisprudence of the ICJ, on preliminary objections) can be appealed to either an arbitral tribunal agreed upon by the state parties to the dispute, or, if no such agreement is forthcoming, to the ICJ (by operation of Article 37 of the ICJ Statute, as the reference in the Chicago Convention is to the PCIJ, adopted as it was in 1944).

We note thus that the road to the International Court of Justice is still open in this case, even if it is a rather winding road. We stress further that the provision of Article 85 of the Chicago Convention is likely not applicable, as it refers to states that have not accepted ‘the Statute’ of the [PCIJ/ICJ], and not to states that do not accept the court’s jurisdiction. All Members of the UN are ipso facto parties to the ICJ Statute, and thus ‘accept’ it. Consent to the jurisdiction of the Court is given by means of their consent to the Chicago Convention and its Article 84. There appear to be no reservations to the Chicago Convention. We shall return to another route to the ICJ in the next section.

Questions of Implementation of Responsibility

Whether invoking Belarussian responsibility under the Montreal Convention or under the Chicago Convention, both injured states (eg Poland) and states ‘other than the injured state’ in the sense of Article 48 of the Articles on State Responsibility may resort to countermeasures in order to implement Belarussian responsibility and induce Belarus to comply with its secondary obligations of cessation, assurances and guarantees of non-repetition, and reparation, as described above.

If it is states ‘other than the injured state’ that will resort to countermeasures, then these would have to be classified as countermeasures ‘in the general interest’, a matter notoriously avoided by the ILC in the ‘no-prejudice clause’ that is Article 54 ASR, but arguably a practice that is much favoured by (at least some) states (and the EU) in the last couple of decades. The interesting thing here is that such countermeasures may take the form of breaches of not just trade and other obligations, but also of breaches of obligations under the Chicago Convention, if calls to avoid Belarussian airspace and to take other relevant measures, reported by the BBC and NYT, are to be believed (and to materialise). This would make for an interesting turning of the tables: in that case, it may be Belarus that resorts to the ICAO Council, much like Qatar did in response to measures taken against it by Saudi Arabia and other states, leading to an appeal to the ICJ in the Appeal Relating to the Jurisdiction of the ICAO Council under Article 84 of the Convention on International Civil Aviation (Bahrain, Egypt, Saudi Arabia and United Arab Emirates v. Qatar), culminating in the Court’s judgment of 14 July 2020.


Depending on further clarification on the facts, it appears likely that Belarus has breached the Chicago Convention as well as the Montreal Convention in forcing FR4978 to land in Minsk. In particular, Belarus breached the Chicago Convention because there appears to have been no reasonable grounds for it to conclude that the Ryanair flight was being ‘used for any purpose inconsistent with the aims of this Convention’. This however is not ‘state hijacking’ or ‘piracy’; it is a breach of Belarusian obligations under the aforementioned international treaties. Even though the route to adjudication is precluded in the case of the Montreal Convention due to Belarusian reservation, it remains open in the case of the Chicago Convention. All states parties to the two Conventions have standing, we argue, to bring claims against Belarus for these alleged violations, and thus also to adopt ‘sanctions’ (countermeasures) against it. Such actions may also fall to be tested in international adjudication.


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Tarcisio Gazzini says

May 24, 2021

Dear Miles and Antonios,
thank you very much for this excellent post and for clarifying so well the legal framework.
In my opinion,however, you've been too far on the point on erga omnes obligations.
Whether erga omnes partes or erga omnes tout court, the essence of these obligations is that they are indivisible (see Arangio-Ruiz's reports on State responsibility). A State cannot comply with them with regard to SOME but not ALL other Parties or other States.
This is hardly the case of civil aviation obligations. The expression "without exception whatsoever" is in my view not enough to change the bilateral nature of these obligations.
Apology if I've missed this point (I'm using my phone), but it could be interesting to consider also the nationality of passengers.

AntoniosTzanakopoulos says

May 24, 2021

Dear Tarcisio,

Thank you for your comment. Certainly a point on which there can be disagreement. Our view, however, is that these are not 'civil aviation obligations'. One is an obligation to refrain from the threat or use of force against civil aviation, which is--as we say in the post--in part an implementation of the obligation under 2(4) UNC. The other is an obligation to prevent certain acts against civil aviation which is coupled with an obligation to criminalise the relevant conduct and coupled with an obligation to extradite or prosecute, creating a net from which there is meant to be no escape among the parties to the treaty. We think that both sets of obligations are established in the collective interest of the group of states-parties to the relevant treaties, and thus EOP. Now whether they can be 'divisible' or not, it depends on what one means. The obligation not to use force for example is in a way divisible, as it can be bilateralised (eg when state A uses force against state B, state B is directly injured by the breach in a way that state C is not--see Article 42 ASR), but at the same it is established in the collective interest, it is owed to the international community as whole, including state C, and thus state C is a state other than the injured state in the sense of Article 48 ASR and can invoke the responsibility of state A as per the ASR. In that sense, we treat EO(P) as referring to standing only and as depending on whether the states making the rule meant to attribute the relevant standing to each other--we do not see it as an inherent property of certain obligations as opposed to others, be they characterised as 'civil aviation' obligations, 'divisible' obligations, etc. We hope that makes sense.

All best wishes,

Antonios and Miles

Martin Scheinin says

May 25, 2021

(Sorry, my finger swiped the "send" button prematurely. Here's the rest of the comment.)

If there was a crime under the 1970 Convention, then the incident was an act of terrorism by Belarusian state agents. The 1963 Tokyo, the 1970 The Hague and the 1971 Montreal Conventions, and the 1988 Protocol to the last-mentioned one, are often listed among counter-terrorism instruments that for the part of their subject-matter define what is meant by terrorism in international law. The 1999 Terrorism Financing Convention mentions many of them (not the 1963 Tokyo Convention though) in its own definition of terrorism in Article 2, providing a legal basis for regarding crimes under the conventions as acts of terrorism.

As Security Council Resolution 1373 (2001) does not provide its own substantive definition of terrorism, one can argue that through Article 2 (a) of the Terrorism Financing Convention and the Annex it refers to, the conduct by Belarusian KGB agents on board the Ryanair plane and by anyone acting in concert with them in the perpetration of those acts, committed an act of terrorism that triggers the obligations of all UN Member States under Article 2 of the Resolution.

Here's what I said about the matter on Twitter yesterday, with some quotes from the sources:

Martin Scheinin says

May 25, 2021

Dear Miles and Antonios,

Thank you for a very informative and compelling blog post. There is one factual issue where my assessment is different, and which then triggers a separate legal issue of interest, at least to those legal scholars who ask whether the primarily political references to "state terrorism" have some credence in international law. Was it an act of terrorism by Belarus?

According to the authors, there is unlawful seizure of an aircraft in the terms of the 1970 The Hague Convention if a person on board an aircraft in flight seizes or exercises control of that aircraft (or attempts to do so) by means of threat or force or through other form of intimidation but that "it does not appear that this happened in the instance". To me it is implausible if not impossible that Belarus would send both its KGB agents on board the plane, and a fighter plane on a mission to intercept the plane, if they were not acting in concert for the purpose of forcing the plane to land in Minsk. Hence, what the KGB agents were doing on the plane, and anyone acting in concert with them in the commission of those acts, appear to have committed a crime under the 1970 Convention (and possibly other related instruments concerning offences on board civilian aircraft).

Chimene Keitner says

May 25, 2021

An impressive analysis on very short notice, but the invocation of ratione materiae immunity seems wrong to me (as does the link to a book on state responsibility for terrorism). There would be no need to resort to arguments about implied waiver, since KGB agents engaged in espionage, assassination, or kidnapping on board an Irish plane are not viewed as acting in their "official capacity" for immunity purposes to begin with. Would be glad to hear from others who have views on this.

Miles Jackson says

May 26, 2021

Hi Martin,

Thank you very much for the comment.

We see the argument as it runs from the Article 1 of the Hague Convention to the annex to the International Convention for the Suppression of the Financing of Terrorism. I think we'd want to see a little more on the factual basis for meeting the conduct element of the definition in Article 1. One worry in particular is whether 'control' is to be understood as broadly as an instruction from ATC, or whether we need factual control to be exercised on the part of agents on board (or whether indeed we can lump together ATC instructions, intercepting aircraft, and mere presence of agents on board together to argue that this constitutes 'exercise of control'). This may render provisions in other treaties redundant, which would point against such an interpretation.

As Professor Joseph noted on your thread on twitter, on an evaluative level this would also leave us with a broad definition of terrorism - one that doesn't include a distinctive purpose. In other contexts, there are good reasons to be nervous about such a broad approach to definition.

Miles and Antonios

Miles Jackson says

May 26, 2021

Hi Chimene,

Thank you too for your comment and question.

On the question of official acts and immunity, the argument you raise has attracted some judicial support - at least some of the judges in the House of Lords in Pinochet adopt it, for instance.

We're not sure that it is right, though, in principle, or that it is generally accepted in practice. Just to focus on principle, it seems to run together (i) whether an act is an official act with (ii) whether that act was wrongful under international law. These are separate questions. It is true that exceptions to immunity ratione materiae might emerge, but that is not because the relevant acts are not official acts.

Happy to discuss more too!


Chimene Keitner says

May 27, 2021

Thanks Miles. Would be glad to take the conversation offline, but commenting here in case other EJILTalk readers are interested (and might also direct them to this ancient post:

Could you refer me to a widespread and consistent state practice of granting foreign officials immunity for kidnapping outside their own territory? I don't see how the KGB officials would have any law enforcement authority whatsoever aboard the Ryanair flight (setting aside whatever happened subsequently on the ground). Moreover, in cases including espionage and assassination (Skripal etc.), there has been no suggestion as far as I'm aware that the perpetrators would enjoy ratione materiae immunity.

Over to you ...

Paula Silfverstolpe says

May 28, 2021

Dear all, thank you all for a very interesting post and comments on the flight incident in Belarus. You mention article 3 bis which entitles the territorial state to demand landing of a civil aircraft flying without authority or if is used against the purpose of the Convention. My understanding is that this article applies to a situation where the operator of the aircraft is knowingly using it in violation of the convention (like espionage) but perhaps not when an ordinary person or a passenger has placed a bomb on the aircraft. I am wondering if the Tokyo Convention on 1963 might not have provided Belarus with a better legal basis had there actually been a bomb onboard or if the aircraft was flying over a restricted area as alleged by president Lukashenko. Article 4 of the Tokyo Convention provides a legal basis for interfering with civil aircraft in five situations: if the offense has an effect on the territorial state, if the offense is committed by or against citizens or permanent residents of the territorial state, if the offense is against the security of the state, if it is against the flight rules of the state, and finally if it is necessary to effect an obligation under an international treaty. Off course this only applies to offenses committed onboard the aircraft and not for other crimes. Military interception of civil aircraft is not a violation of article 3 bis or even article 2.4 of the UN charter provided it is done in accordance with Annex 2 of the Chicago Convention:
a) interception of civil aircraft will be undertaken only as a last resort;
b) if undertaken, an interception will be limited to determining the identity of the aircraft, unless it is necessary to return the aircraft to its planned track, direct it beyond
the boundaries of national airspace, guide it away from a prohibited, restricted or danger area or instruct it to effect a landing at a designated

Interestingly, the Swedish law allows the air force to carry out interceptions against civil aircraft in certain highly restricted circumstances.Off course all measures including interception must be done in a way that minimizes the risk to passengers and the aircraft in question.

The other question is about the legality of the "air blockade" that is being imposed by the EU against Belarus as a reaction to the incident. It makes me think of the case against Saudiarabia, UAE, Bahrein and Egypt before the ICAO Council and the decision by the ICJ last year in this case where Qatar alleged that the quartet violated the Chicago Convention when it imposed an air blockade (since 2017) against Qatar as a countermeasure for Qatar allegedly sponsoring terrorism in the region.

Best regards,

Paula Silfverstolpe

Miles Jackson says

May 28, 2021

Hi Chimene,

Thanks for this and for the link - very interesting.

On the general issue, our difference might be one of starting points - as you note in your Fordham piece linked in the post you mentioned above.

In our view, the question is whether there is reason to think that there is an exception to the ordinary rule of immunity attaching to the conduct of state organs. In principle, state practice might ground such an exception - but that would need to be demonstrated. Could the opposite starting point be a workable - for any specified official act there needs to be a demonstration of practice and opinio juris to bring that act specific act within the immunity rule?

On the specific instance, on the face of the reported facts Belarusian agents don't appear to be acting outside of the state's territory.

Miles and Antonios

Martin Scheinin says

May 28, 2021

Hello Miles and Antonios,

Thanks for engaging. Your response of 26 May is related to both of my points. As to the first one, it is really a factual issue what the KGB agents were actually doing on board the plane. The news reports are in part unclear or conflicting here, and I am not in a position to verify them. So, I have to (re)phrase my argument as follows: assuming that they were actively and in a coordinated fashion involved in a plan to compel the plane to land in Minsk, which also happened in part as a consequence of their actions, their conduct should be assessed under international instruments related to offences on board a civilian aircraft, including The Hague Convention and its Article 1.

The second question is whether such offences would then qualify as "terrorism", for instance for purposes of Security Council Resolution 1373 (2001), even without one of the two distinctive purposes of terrorism usually included in international instruments (taking of hostages or creating fear among the population). In my view you are right in being hesitant about any new widening of the notion of terrorism in international law. But this does not change the fact that the 1999 Terrorism Financing Convention qualifies as terrorism crimes as defined in enumerated treaties concerning crimes on board civilian aircraft, irrespective of whether there was a distinct terrorist purpose or not. Instead, it attaches the distinctive purpose requirement only to crimes not defined in pre-existing treaties listed in its Annex.

Were the usual distinctive purposes of terrorism perfectly clear and enjoying moral and legal authority, I would rely on them to contest a wide application of the civil aviation instruments for extending the notion of terrorism. But as the two distinctive purposes are not very good in defining what terrorism is, I prefer to suggest, instead, a threshold requirement based on the gravity of the offence.

All best wishes, Martin

Dmitrii Kouznetsov says

May 29, 2021

Dear Miles Jackson.
Dear Antonios Tzanakopoulos.
Thank you for the links and the analysis.
I still have doubts about bomb on board of Boeing 737-8AS performing regular flight FR4978 2021.05.23.
I think, the agents of the Belarus KGB could load the bomb with GPS, that activates it at coordinates of Vilnius, and withdraw that bomb at Minsk.
In the similar way, 2010.04.10, the Polish aircraft could been bombed ("Katyn-2") by the Russian KGB agents; the pilots had no chance to land it at "Severny" airbase.
I think, the European security staff could be more efficient in revealing agents of KGB and catching them. For example the "Boshirov and Petrov" were easy to calculate from internet, as they have no home, no job, no relatives, no car, no telephone registered in a database, nor any article published and signed by their names (only the fake passports); they could be captured with their "novichok".

Miles Jackson says

May 31, 2021

Hi Paula,

Thank you very much for your comment.

I will look again at Article 4 of the Tokyo Convention. Agreed - it will be interesting to see what develops before the ICAO Council.