1.2.1 Historical Background

As early as 1919, the Treaty of Versailles hinted at a general desireFootnote ² for an international instrument regulating the regime of ports. In this respect, the 1923 Convention and Statute on the International Régime of Maritime PortsFootnote ³ is a landmark development in the global regulation of ports. It primarily addresses the issue of equality of treatment concerning freedom of access to ports, the use of ports, and availing of benefits regarding the navigation and commercial operation and use of port facilities (see Article 2). In this respect, Article 2 of the Convention’s Statute requires the contracting parties to ensure equal treatment of vessels from other State parties regarding the freedom of entry to ports. Although PSJ is not explicitly mentioned, it also refers to the general competence of port authorities (Articles 3 and 4).

Before the 1970s, in the absence of a directly applicable clear treaty rule, port States exercised restricted jurisdiction over foreign vessels under customary law, which was mainly in the form of denying entry to their ports or imposing specific conditions on foreign vessels. It is submitted that the concept of PSJ emerged in the 1970s. In particular, the 1973 Inter-Governmental Maritime Consultative Organisation (IMCO) Conference on Marine Pollution and the 1974 Conference of the International Law Association (British Branch Committee on the Law of the Sea) appear to be early examples. At the IMCO Conference, the US proposed a draft that would allow port States to ensure compliance with global regulations. However, the proposal was not accepted (Marten Reference Marten2014, 33–35; Qi and Zhang Reference Qi and Zhang2021, 19–21). Over time, it became evident that the international shipping regulations set out in the IMO’s major instrumentsFootnote ⁴ could only be enforced by expanding the powers of port States (Özçayir Reference Özçayir2004, 74–77).

Significant developments in the evolution of PSJ occurred in the 1980s, particularly with the adoption of UNCLOS and the Paris Memorandum.Footnote ⁵ Notably, port States have assumed a critical role in ensuring compliance through various regional port State control agreements. UNCLOS (see Article 218) implicitly recognizes PSJ without providing an explicit definition, and it acknowledges the port State’s authority to set conditions for foreign ships to have access to ports. Additionally, UNCLOS enables port States to physically inspect if a ship’s actual conditions do not match its documentation. The evolution of PSJ was further enhanced in 1984 with the entry into force of the International Convention on Standards of Training, Certification, and Watchkeeping for Seafarers (STCW),Footnote ⁶ which grants port States the authority to detain ships until any deficiencies posing risks to people, property, or the environment are addressed. The evolution of PSJ has continued at both the regional and global levels; for instance, the IMO adopted the first version of Resolution A.472(18) in 1993, which set procedures for port State control (Marten Reference Marten2014, 2–3, Reference Marten2016, 471; Özçayir Reference Özçayir2004, 74–77; Qi and Zhang Reference Qi and Zhang2021, 25–26). Over time, the myriad of IMO legal instruments enhanced the PSJ regime. Finally, the “no more favourable treatment” clause, which is usually incorporated into IMO Conventions, further consolidated PSJ vis-à-vis FSJ.

1.2.2 Legal Basis of PSJ

Port States possess regulatory and enforcement authority over foreign ships in their ports. As a fundamental principle, a port State, therefore, can necessitate compliance with its national regulations for foreign vessels, provided these do not pertain to aspects entirely internal to the ship. In this context, PSJ refers to the authority of a State over ships that voluntarily visit its ports (Ringbom Reference Ringbom2011, 620–623). As a public law concept, PSJ is a direct extension of the principle of State sovereignty and is primarily a form of territorial jurisdiction, though it encompasses additional aspects.Footnote ⁷ Over time, PSJ has transformed from a voluntary application in specific areas to a more comprehensive and obligatory implementation largely through IMO instruments and their broadening reach to new areas (IMO 2023c, 9–10; Kopela Reference Kopela2016, 93–94; Marten Reference Marten2014, 1, 7, 20–21; Molenaar Reference Molenaar, Freestone, Barnes and Ong2006, 208–209; Sumer Reference Sumer2023b, 117).

PSJ is broadly viewed as allowing port States to exercise significant regulatory authority over foreign-flagged ships. In a nutshell, PSJ provides a mechanism for corrective action if flag States fail to meet their obligations. Although its significance has faded due to the expanding PSJ, FSJ remains a foundational mechanism for maintaining legal order at sea, especially on the high seas. However, over time, in response to the inadequacies of flag States in ensuring compliance of their ships, port States had to step in, and indeed, they have increasingly taken on a supplementary, if not leading, role (Derrig Reference Derrig2022, 534–536; Qi and Zhang Reference Qi and Zhang2021, 8–9).

While UNCLOS predominantly upholds FSJ over vessels, it also recognizes the growing significance of port States in ensuring adherence to international rules and standards. Indeed, the notion of the port State as a separate jurisdictional entity gained importance with the adoption of UNCLOS. However, UNCLOS, as an umbrella instrument, does not codify the scope of PSJ comprehensively. Nonetheless, it provides a legal basis, particularly in Article 218, “Enforcement by port States” (see also Articles 211(3) and 219), which also points to the IMO as the competent international organization (CIO). Acting as the secretariat for UNCLOS, the UN Division for Ocean Affairs and the Law of the Sea compiled a table elucidating the implications for the “competent or relevant international organizations” in relation to UNCLOS for ocean governance. That document, which was published in the Law of the Sea Bulletin No. 31, also confirms that the IMO is the CIO in the context of Article 218 (IMO 2014, 7–8; Marten Reference Marten2014, 2–3; OECD 2001, 28; Sumer Reference Sumer2023b, 125–126; United Nations 1996).

The authority of a port State on foreign-flagged ships docked at its ports is crucial to the routine operations of international shipping. Although States have historically exercised territorial sovereignty over their ports, the concept of the port State as a distinct jurisdictional entity was formally established by UNCLOS. In establishing the legal framework for the rights and obligations of port States, UNCLOS heavily relies on the international rules developed at the CIO. By incorporating the IMO’s regulations through rules of the reference system, UNCLOS indeed grants a significant role to the standards adopted under the auspices of the organization (Marten Reference Marten and Ringbom2015, 5–6, 109–112; Sumer Reference Sumer2023b, 139–140).

Given that UNCLOS is relatively silent on PSJ, any limitations regarding the subject matter or scope of regulations in this context must be sought outside of the Convention. This is supported by the preamble of UNCLOS, which emphasizes that matters not explicitly regulated by the Convention continue to be governed by the general international law (Marten Reference Marten and Ringbom2015, 109–112).

UNCLOS serves as the primary international legal framework, establishing the rights and obligations of States. States assume their roles as coastal, flag, and port States based on various factors, such as their geographical location, sovereignty, boundaries, and functions, as well as the treaties to which they are parties. Typically, a coastal State’s authority diminishes as the distance from the shore increases (Beckman Reference Beckman2007, 326; Mansell Reference Mansell2009; Wolfrum Reference Wolfrum2014). Article 8 of UNCLOS establishes that waters on the landward side of the baselines are part of internal waters. This recognition affirms the sovereignty of port States over the waters in their ports. Furthermore, Article 25 reaffirms the right to regulate access to internal waters, including ports. Moreover, UNCLOS strengthens the powers of port States in protecting the marine environment, allowing them to regulate the access of vessels into their ports, inspect vessels for compliance with port entry requirements, and deny access to noncompliant vessels (Galani Reference Galani2021, 609). In general, Articles 211, 218, and 219 address PSJ. Article 211(3) primarily sets the foundation for the State’s jurisdiction to adopt domestic rules. On the other hand, Articles 218 and 219 specifically outline the port State’s enforcement authority. In essence, while Article 211 focuses on the authority to legislate, Article 218 addresses the authority to enforce such legislation (Keselj Reference Keselj1999, 131–135; Özçayir Reference Özçayir2004, 80–81).

As a framework convention, the UNCLOS emphasized general principles of the law of the sea, leaving broader discretion to States rather than restricting interpretation or hindering technological development. It was undoubtedly drafted for crewed ships. However, this does not mean that the drafters intended to exclude new types of vessels (Sumer Reference Sumer2023b, 138; Veal et al. Reference Veal, Tsimplis and Serdy2019). Indeed, the UNCLOS regime is designed to evolve and address emerging issues that could not possibly have been foreseen during the adoption of UNCLOS. Therefore, it is suggested that the norms and principles regulating conventional manned vessels may apply to MASS with the necessary adjustments. In this context, Kraska aptly opines that the current legal framework for the law of the sea already offers a fundamental structure for regulating MASS (Kraska Reference Kraska2010, 44–45).

1.4.1 Construction, Design, Equipment, and Manning Standards

The primary regulatory approach to enhance the safety of shipping and to control pollution from ships involves setting standards pertinent to the construction, design, equipment, and manning of ships (CDEM standards), as in the example of SOLAS and MARPOL (Churchill Reference Churchill2016, 443). This particularly merits closer scrutiny, given the varying qualifications of MASS compared to traditional ships.

In accordance with relevant IMO Conventions, States may adopt measures that require vessels to adhere to CDEM standards as both entry criteria and rules to be followed while in ports. The application of prescriptive jurisdiction regarding CDEM standards that extend beyond international legal requirements causes issues due to their extraterritorial effect. Naturally, vessels must meet these standards as a continuous activity throughout their journey, even before approaching port. Thus, CDEM requirements need to be met on the high seas before and after the port visit, suggesting an exercise of extraterritorial jurisdiction. Nevertheless, it is submitted that the extraterritorial impact of these measures is merely incidental, not the primary objective of the port State’s domestic laws. Such static features are attributes that remain consistent regardless of a ship’s location, meaning that a ship either complies or does not comply with them wherever it is, whether in port or not. Since these features cannot easily be modified during a voyage, they are often seen as the most intrusive in relation to a ship’s navigational rights. Nonetheless, ships have the option of visiting a port. But, if they choose to do so, then, naturally, they must adhere to the CDEM standards set by the port State (Churchill Reference Churchill2016, 454–556; Kopela Reference Kopela2016, 95–96; Marten Reference Marten2016, 472–473; Ringbom Reference Ringbom2011, 620–623).

Port States have the authority to set CDEM standards for foreign ships intending to have access to their ports. It follows that port States can enforce these CDEM standards within their ports. Given that PSJ is fundamentally territorial, it stands to reason that a port State can, in principle, require foreign MASS that call at its ports to adhere to CDEM standards. The IMO Conventions often mandate port States to adopt and enforce such standards. A port State may also opt to avoid stringent CDEM measures if it values the economic benefits derived from foreign ships, including MASS, such as port fees and charges for services, and wishes to maintain its attractiveness as a port of call (Churchill Reference Churchill2016, 446–448, 467–469).

Given that ports are considered part of a State’s territory, port States have the authority to set CDEM standards for vessels calling at their ports. They may set more stringent CDEM standards than IMO standards unless there exist specific IMO Conventions or unless international laws stop them. Essentially, PSJ is subject to three key limitations with regard to CDEM standards. First, port States must respect the immunity of foreign warships and government-owned ships engaged in noncommercial activities. Second, various treaties mandate that States should not discriminate between ships based on nationality. And, finally, pursuant to Article 211(3) of UNCLOS, port States are obliged to provide due publicity to CDEM measures (Churchill Reference Churchill2016, 467–469).

Vessels can choose to ignore a port State’s regulations by not entering its ports. However, by deciding to visit a port, vessels implicitly agree to comply with the entry conditions, even if these conditions concern activities that occurred outside the port State’s territorial jurisdiction. In light of the foregoing, skeptical port States can indeed prescribe CDEM standards to deny access to MASS, unless the IMO’s GAIRS (see UNCLOS, Article 21(2)) restrict this power. Indeed, a key limitation is that a port State cannot establish CDEM standards that conflict with IMO Conventions that it has ratified, as doing so would breach its treaty obligations (Churchill Reference Churchill2016, 450–452; Ringbom Reference Ringbom2011, 626–628).

1.4.2 The Location of the Remote Operation Centers

According to the draft MASS Code, remote control involves operating the MASS or certain of its functions from a remote operation center (ROC). Under the Code, “ROC” means a distant location from the MASS that can control some or all aspects of the MASS functions. In this vein, the draft code defines a “Remote Operator” as a qualified person who is employed or engaged in operating some or all aspects of the MASS functions from a ROC. And, notably, “Remote Master” is a master in a ROC (IMO 2024b, annex I, 11).

The said new actors and terms cause some legal ambiguities. In particular, the location of a ROC can lead to intricate legal challenges concerning jurisdiction and the responsibilities of the flag State. For instance, customarily on the high seas, ships have been subject to the exclusive FSJ based on the view that vessels are essentially extensions of a flag State’s territory. But this reasoning would be difficult to follow for ROCs, which are hosted in another State, due to the overlap between the territorial jurisdiction of the State hosting the ROC and the jurisdiction of the flag State. There can be several related issues if the ROC is situated in a country other than the flag State with regard to ensuring the effective FSJ requirement under Article 94 of UNCLOS. Evidently, the legal tension will be less if a ROC is in the territory of the flag State. Although, at first sight, it seems plausible to ensure that ROCs are located only in the flag States, there is no such obligation in the law of the sea regime (Ishii Reference Ishii2023, 268–269). Therefore, the legal status of ROCs is likely to become a contentious issue until the IMO clarifies the issue by developing a common understanding between flag and port States (Yoo and Shan Reference Yoo and Shan2019, 563).

Once registered, the flag State is bound under Article 94 to exercise effective jurisdiction and control to ensure that the registered vessel complies with the IMO’s GAIRS. However, a critical issue arises with MASS: how the flag State can effectively oversee the remote operators to fulfil these obligations. Unlike manned ships, where the flag State can exert jurisdiction over both the vessel and the individuals on board, ROCs present unique legal complexities due to the absence of onboard crew and their presence elsewhere. Hence, the location of the ROC introduces intricate jurisdictional challenges. Notably, there may be overlapping jurisdictions between the State where the ROC is situated and the flag State. This issue can be further exacerbated depending on the legal characterization of the State in which the RCS is operated. For instance, the host State can be either a port or a coastal State, or both. Furthermore, the host State can be a landlocked State as well. Should this be the case, perhaps analogously to the presence of the dry ports, landlocked host States can arguably be considered as port States. There can be some legal creativity to address the issue in this manner, but, on the other hand, it is clearly not within the IMO’s mandate to come up with a new jurisdictional role, such as host State and/or ROC State jurisdiction, given that there is no such concept under UNCLOS. Evidently, when the ROC is within the flag State’s territory, it can exercise both prescriptive and enforcement jurisdiction. In contrast, if it is in the territory of a different State, then the flag State’s jurisdiction and reach are significantly limited, preventing it from enforcing its laws against the individual in the foreign jurisdiction without that State’s consent (Dong et al. Reference Dong, Bautista and Zhu2024, 2).

As a corollary to this, there seem to be increasing concerns about enforcing regulations against ROCs abroad. Considering the legal complexities of a ROC situated in a different State from the flag State, some delegations at the IMO suggested that discussions should focus on scenarios where the ROC is within the flag State’s territorial jurisdiction. However, other delegations argued that restricting the discussions in this way would impose an impractical limitation. The MASS Joint Working Group (JWG) subsequently agreed that the jurisdictional issue, including the conditions concerning a ROC located outside the flag State, should be reviewed by the IMO’s Legal Committee (LEG; IMO 2024h).

Indeed, in the absence of bilateral arrangements or the IMO’s GAIRS, flag States may face considerable limitations in meeting their international obligations when the ROCs are in different countries. For instance, the flag State may struggle to acquire necessary data for investigations due to a lack of cooperation or restrictions imposed by the State where the ROC is located (Ishii Reference Ishii2023, 281–284). Despite the abovementioned challenges, this is probably not a deal-breaker or a game-changing development hindering the integration of MASS. Indeed, the current legal architecture, including the trends toward stronger PSJ to ensure compliance, permits flexibility to address FSJ issues, as will be explained later.

1.4.3 Ship as a Unit Concept

It is a truism that the definition of “ship” varies depending on the subject matter and context of the convention in which it is mentioned. The terms “ship” and “vessel” are defined differently in various conventions adopted by the IMO, according to their scope of application and their objectives. At times, drafters of the legal instruments even attempted to avoid definitions so as not to confine the treaty texts to limited maneuverability spaces, as in the example of UNCLOS. Indeed, considering that UNCLOS aims to regulate all issues relating to the law of the sea, a single definition of “ship” would be neither feasible nor beneficial. On the definition issue in relation to the MASS concept, Kraska rightly observes a common aspect: that human control versus autonomous/remote control does not determine what constitutes a ship. Indeed, pursuant to Article 91 of UNCLOS, States have the discretion to fix the conditions for the granting of their nationality to vessels. In this regard, Kraska also maintains that registration of MASS is subject to national law (Kraska and Pedrozo Reference Kraska and Paul Pedrozo2023, 41–44; Petrig Reference Petrig, Johansson, Fernández, Dalaklis, Pastra and Skinner2023, 83–84).

The International Tribunal for the Law of the Sea (ITLOS) has firmly refined the definition of a ship in a few cases, including the M/V “Saiga” (No. 2) case,Footnote ¹² the M/V “Virginia G” case,Footnote ¹³ and the M/V “Norstar” case (Preliminary Objections).Footnote ¹⁴ In each of these cases, the respondent raised multiple objections regarding the admissibility of the flag State’s claims, particularly focusing on the nationality of the claims. In all instances, ITLOS dismissed the objections and proceeded to evaluate the merits of the case. Through these rulings, ITLOS emphasized the distinct identity of a ship as a single unit, highlighting the flag State’s right to pursue compensation on behalf of crew members who are not its nationals and underscoring the broader implications for maritime law. For instance, in countering the argument that a flag State cannot seek redress for crew members who are not its nationals, the Tribunal in M/V “Saiga” (No. 2), upon reviewing UNCLOS, clarified that (Heidar Reference Heidar2024):

ITLOS reaffirmed its jurisprudence in the M/V “Virginia G” case:

ITLOS reached these decisions by considering the practical elements that reflect modern maritime practices, such as the multinational and temporary composition of ship crews and the diverse interests associated with the cargo carried by a single vessel (Heidar Reference Heidar2024). Although it may be too early to consider that the ship as a unit concept can be extended to ROCs, nonetheless, it may be a useful tool to mitigate the legal tension with Article 94. Indeed, given the fact that ROCs are expected to be inherently crucial in the steering of RCS, this necessarily follows the line of thought that ROCs can perhaps be considered under the “unity principle,” even if they are located in other States (Ishii Reference Ishii2023, 268–269). However, this does not necessarily mean that there would be effective compliance mechanisms for ROCs in practice. In this context, in addition to treating ROCs as inherent parts of single units, equivalent to ship bridges, they could arguably be subject to more robust PSJ and constant port State control inspections, which would alleviate the inadequacy of flag States.

1.4.4 Latest Developments at the IMO

The IMO’s Maritime Safety Committee (MSC), the LEG, and the Facilitation Committee (FAL) conducted an RSE for the IMO Conventions under their remit to analyze the compliance issues. The RSE of the MSC and the LEG was concluded in 2021 and that of the FAL in 2022. The RSE is regarded as an important milestone in paving the way for further regulatory action with a view to adopt a goal-based MASS Code (IMO 2021).

In 2023, the MASS JWG aptly agreed that a human master should always be in charge of a MASS and should be able to reassume control when needed, irrespective of its degree of autonomy. Moreover, depending on the technology used on the MASS, the human master may not need to be on the vessel, which suggests that the human master can be a remote master located in the ROC (IMO 2024h). This is, indeed, noteworthy, as it practically corrects the shortcomings of degree four.

Currently, the development of the nonmandatory goal-based MASS Code has been limited to MASS cargo vessels (IMO 2024h, 8). The draft preamble of the MASS Code notes that specific operational functions may be controlled from a remote location and addresses necessary aspects of ROCs (4). To prevent discrepancies and ease the legal tension of the new MASS Code with UNCLOS and international law, particularly given the novel nature of the subject matter, the following text is suggested for inclusion in the MASS Code:

Notably, the current draft Code obliges flag States for the certification and verification of ROCs. It stipulates that every vessel to which the Code applies should have a valid MASS Certificate (para. 6.1). Similarly, every ROC needs to be issued a MASS ROC Certificate (para. 6.2). Moreover, the draft Code states that every administration notified by a company of its intent to operate a MASS should, as it finds practical and necessary, either independently or in collaboration with other contracting governments provide its requirements, procedures, and guidelines for incorporation of the ROC in the verification and certification process of the Document of Compliance (DoC) and Safety Management Certificate (SMC). The process for issuing the DoC is expected to include at least one assessment of the ROC during the DoC’s validity period. This assessment should be conducted by the flag State administration, a recognized organization (RO), or another contracting government at the administration’s request. The DoC should only be valid for MASS if explicitly stated in the DoC. According to the draft Code, the SMC should be issued in line with SOLAS (Chapter IX, Regulation 4.3) and the ISM Code (Part B, paras. 13–15). The SMC should specify the type of ship, indicate that it is operated as a MASS, and identify the ROC, if applicable, involved in the operation of the MASS (IMO 2024h, annex 1, 19–22).

The draft Code also has provisions on Minimum Safe Manning Document (MSMD), for MASS and ROC, in accordance with IMO Resolution A.1047(27) (IMO 2011), as amended, and to the satisfaction of the administration. In this respect, the MSMD for the MASS may show a total manning number of zero linked to specific MASS and reference personnel training and certification requirements as specified in the Code (IMO 2024h, annex 1, 19–22).

It is noteworthy that several IMO member States (Belgium, Liberia, and the Republic of Korea) recently proposed that the MSC consider the following principles for the drafting of the MASS Code: the flag State of the MASS should determine and be responsible for the verification, survey, and certification of the MASS and its ROC; an oversight system, similar to the ISM Code, should be applied to the management certification of ROCs and MASS; the responsible ISM company for the MASS should retain its responsibilities and be certified in accordance with the ISM Code; and the management of remote operations should align with the duties and responsibilities of ISM companies. Cosponsors also proposed a system called “Remote Operations Management” (ROM), with ROM being the management structure for ROCs established by the MASS Code. In this regard, it is proposed that a ROC should be operated by a ROM company holding a ROM DoC. Moreover, MASS should be operated by a ROC holding a ROC Management Certificate. One ROM company could operate one or more ROCs under one ROM DoC, which should be issued by the administration, by an RO, or at the request of the administration by another contracting government in line with the principles of the ISM Code (IMO 2024a).

Furthermore, Belgium and the Republic of Korea, in their joint document submitted to the LEG, endorsed the previous proposal by noting that the ROM system aims to ensure the completion of tasks and responsibilities specific to ROCs. Within this framework, the flag State would verify that a ROM company complies with its safety and security regulations. Like the ISM model, a ROM company could be granted a DoC, and a ROC could be awarded a ROC Management Certificate. The system is flexible enough to allow ISM companies to operate their own ROCs, thereby functioning as ROM companies. Although not directly tackling jurisdictional and ensuing compliance challenges, the ROM concept appears to provide a practical path forward for mitigating FSJ issues (IMO 2024c).

Remarkably, the current version of the MASS Code, which is drafted by the MSC, appears to presume that the duties of flag States would be applicable to MASS. The initial version of the MASS Code draws upon the framework established in SOLAS and the ISM Code for the survey and certification of ROCs. In this regard, it specifically mandates that flag States carry out the survey of ROCs. When a MASS is remotely controlled from an onshore ROC, given that remote operators will replace the traditional master or crew on board, the flag State must oversee these ROCs to ensure proper performance, particularly if they are within the flag State’s territory. For instance, pursuant to the ISM Code, to ensure an international standard for the safe management and operation of ships and for pollution prevention, flag States must conduct surveys and verify companies irrespective of their location. According to paragraph 13 of the ISM Code, vessels should be operated by a company that has been issued with a DoC as evidence that the company is capable of complying with the requirements of the ISM Code (paras. 13, 14). That DoC is issued either by the administration or by an RO, or, at the request of the administration, by another contracting government to the Convention to any company complying with the requirements of the Code. However, the flag State may certainly encounter challenges in overseeing ROCs located in other countries (IMO 2024d).

Japan submitted a paper to the MASS JWG with a view to stimulating further discussion on the scenario where a flag State conducts an inspection to certify and verify a ROC located in other jurisdictions. Such an action, if it is conducted with the consent of the State where the ROC is located and adheres to the provisions outlined in the new MASS Code concerning ROCs, is posited not to encroach upon the sovereignty of the State. Indeed, according to SOLAS, it is broadly recognized that a flag State’s inspection to certify and verify a ship management company under the ISM Code and SOLAS does not violate the sovereignty of the State that hosts the ship management company as a SOLAS State party. In light of the above, Japan observed that a flag State’s certification and verification of a ROC under the MASS Code would not infringe upon the sovereignty of the State where the ROC is operating (IMO 2024d).

During the previous LEG meeting, IMO member States engaged in an extensive discussion on whether the potential arrangements for ROCs, especially those located in a territory different from the flag State of the MASS, fulfill the obligation laid down in Article 94 of UNCLOS. There have also been diverging positions among the IMO delegates during the discussions. For instance, the Argentinian delegation, which seems to have had a more cautious approach to MASS, expressed significant concerns regarding whether the freedom of navigation under the law of the sea regime extends to vessels with higher levels of autonomy. Remarkably, Argentina emphasized its right to regulate the entry of MASS into its jurisdictional waters. In this context, notably, Argentina also referred to Article 25 of UNCLOS, which grants the authority to States to impose restrictions on the entry of foreign ships into their ports or territorial sea (IMO 2024f).

During the subsequent discussion, several member States expressed their concerns about the ability to meet the standards for the effective exercise of FSJ when MASS are controlled by ROCs situated in countries other than the flag State. Delegates raised several notable points: UNCLOS does not allow the transfer of flag State responsibility to ROCs located in other countries; if the ROC operating a MASS is situated outside of its flag State, significant questions arise regarding the flag State’s capacity to maintain effective control over the ROC; the host State, which may have territorial jurisdiction over the ROC but no related obligations under UNCLOS, might not have a clear role; these jurisdictional uncertainties create ambiguity for flag, port, and coastal States about which country exercises jurisdiction over a MASS; this could dilute the flag State’s responsibilities to a more symbolic level, inconsistent with UNCLOS; ROCs located outside the flag State would not fall under the flag State’s effective jurisdiction; flag States might not have adequate access to ROCs situated in other countries; and applying the ISM Code model may not be sufficient to ensure effective access and oversight, thus necessitating bilateral or multilateral agreements.

Conversely, several States argued that locating a ROC abroad does not inherently weaken the jurisdictional connection. They claimed that such an arrangement is already grounded in existing maritime practices and legal frameworks. They supported the application of the ISM Code model to MASS operations through ROCs by noting that existing IMO instrumentsFootnote ¹⁵ already provide the framework for flag State oversight. Moreover, those States further expressed that currently international shipping operates efficiently with minimal physical ties to a flag State’s territory; flag States frequently oversee the operation of their ships by establishing offices in different parts of the world; and, as international law does not require the physical presence of a vessel or its associated entities within a flag State’s territory, it would be unusual to claim that ROCs must be located solely within the territory of the flag State (IMO 2024f).

Notwithstanding the positive approach of some member States that are also expected to be the leading MASS technology providers, uninterrupted shipping requires a broader consensus, including port States.

1.5.1 International Trade Law on Port States and MASS

As discussed earlier, port States can impose stricter standards than IMO norms as conditions for foreign ships to enter their ports. These high standards can regulate the behavior of foreign ships within the port area and may naturally extend to their actions outside the port before entering. Thus, through domestic laws, port States can indirectly establish extraterritorial jurisdiction over foreign ships, which is critical in the context of MASS. This can hinder MASS operations and may eventually lead to hidden trade barriers and discriminatory practices (Chen Reference Chen2023).

Even though port States usually have broad discretion under IMO and International Labour Organization instruments, this discretion can be considerably limited by bilateral or multilateral trade law treaties to which a particular port State might be a party. The most significant limitations to PSJ may originate from international trade law rather than UNCLOS. International trade treaties under the World Trade Organization (WTO) can impose restrictions on PSJ. Since PSJ can restrict international trade, particularly in goods, it could potentially conflict with WTO law – specifically the General Agreement on Tariffs and Trade,Footnote ¹⁷ which includes the principles of freedom of transit (Molenaar Reference Molenaar, Freestone, Barnes and Ong2006, 202; Ringbom Reference Ringbom2011, 632–637; Ryngaert and Ringbom Reference Ryngaert and Ringbom2016, 386–388).

1.5.2 Facilitation Committee

For the operation of RCS, technology is expected to be increasingly responsible for information sharing with the flag, coastal, or port State authorities. Indeed, remote operation requires accurate, up-to-date data and reliable communication systems. The IMO’s Facilitation Committee (FAL), which is tasked with addressing the facilitation of international shipping, concluded its RSE at the Facilitation Convention (FAL 46) in 2022 (IMO n.d.-a).

The outcome of the FAL’s RSE noted that a new type of certification and identification for MASS operations would be required for the new duties. In this respect, it is indeed important to take the procedures for declarations made on arrival and departure into account. FAL also identified certificates and other documents and the sharing of information as high-priority cross-cutting issues. Regarding the requirements for the arrival, stay, and departure of ships to and from ports, shipowners must present their certificates and other documents related to registration, measurement, safety, manning, and similar matters to public authorities. Hence, the relevant certificates, documents, and data may need to be amended if new certification requirements for RCS are developed (IMO 2022, 2024d). The future work of FAL can be instrumental in mitigating the concerns of port States, as well as facilitating the operation of RCS.

1.6.1 Definition

The conditions that ships encounter in the high seas naturally differ significantly from those in port areas. In ports, there is usually high traffic density. Additionally, tides, shallow waters, and other unique port characteristics can present higher navigational hazards than in open seas. Therefore, pilotage is indeed necessary, as it offers local knowledge. Essentially, a pilot possesses specialized knowledge of local conditions and navigational hazards and is typically brought aboard a vessel at a specific location to navigate or guide the ship through a particular channel or river, or enclosed waters, to or from a port. A “pilot” is defined as an individual who possesses specialized knowledge of local navigation conditions and potential hazards (Agripino de Castro Reference Agripino de Castro, Pasold, Attard, Fitzmaurice, Martinez, Arroyo and Belja2016, 423; Aucoin Reference Aucoin2024, 22–23).

1.6.2 Interplay between Pilotage and MASS

Pilotage services, while often seen as specialized services for shipping, also function as public services due to the significant potential risk of accidents and groundings. The success of pilotage service rests on effective communication and information exchange among the pilot and the master. At times, pilots already provide guidance remotely from shore via radio communications as well. Regardless of the method, MASS integration is likely to significantly transform the nature of pilotage operations. But, in any event, it is clear that an RCS would greatly benefit from a pilot’s insights; moreover, pilotage can serve as a reassurance for port States. The extent and direction of these changes will largely depend on technological advancements in this field. Regardless of these developments, the value of a local guide remains clear; a remote master will undoubtedly benefit from the expertise of a pilot familiar with the local maritime environment (Aro and Heiskari Reference Aro and Heiskari2018, 28–29; Uğurlu et al. Reference Uğurlu, Kaptan, Kum and Yildiz2017; Van Hooydonk Reference Van Hooydonk2014, 416).

Notably, the pilotage service is not exclusively governed by an international instrument, making the legal landscape complex. The legal status of pilots and the performance of pilotage services are regulated by domestic laws. Therefore, guidance should be sought from domestic laws until the situation changes. Typically, such laws grant local ports the authority to regulate and establish pilotage requirements at a local level. Consequently, even in a single country, different ports may have distinct pilotage requirements. Such local regulations often vary and may not be consistent even at the national level, let alone regionally or internationally. Ehlers notes that these services are thus far typically provided within national waters, especially in internal waters. Hence, the international law of the sea has only occasionally influenced pilotage in specific cases (Black Reference Black2020, 12–13; Ehlers Reference Ehlers2024).

According to the UK Pilotage Act 1987, pilot means any person not belonging to a ship who has control of the ship. Under the Maltese Maritime Pilotage Regulations, “pilotage” means the act performed by a licensed pilot to assist the master during navigation and maneuvering when entering, departing, or shifting in port areas (Article 3). The Danish Pilotage Act allows shore-based pilotage. It defines “pilotage” as navigational advice regardless of whether the advice is provided to the master on board the vessel or by means of communication from a distant location (Davies Reference Davies, Ringbom, Røsæg and Solvang2020, 281–282).

Remote pilotage is applicable to any ship but is particularly pertinent to MASS. These vessels are likely unable to utilize traditional pilotage services – where a pilot physically boards the ship to provide navigational advice – due to physical and technical constraints. For degree two ships, which have onboard crews, complying with local pilotage requirements will be a straightforward task due to the presence of crew. Degrees three and four ships, which operate without any onboard crew, present unique challenges for pilotage. For these vessels, pilotage options may need to include shore-based pilotage, where a pilot remotely guides the ship from land (Danish Maritime Authority 2017, 21; Davies Reference Davies, Ringbom, Røsæg and Solvang2020, 284–286). Indeed, there is no legal requirement for the pilot to be physically on board the vessel to which they are rendering their services. Besides, it would be impractical for a pilot to board an RCS unless necessitated by urgent circumstances or domestic regulations. For these types of vessels, pilotage services are likely to be provided remotely. For instance, Finland has recently enacted legislation that permits pilotage to be conducted remotely (Soyer et al. Reference Soyer, Tettenborn and Leloudas2022, 12–13).

The IMO Assembly, in 2003, adopted a resolution on “Recommendations on Training and Certification and on Operational Procedures for Maritime Pilots Other Than Deep-Sea Pilots.” This nonbinding resolution acknowledges the crucial role of pilots in enhancing maritime safety and protecting the marine environment. In particular, the IMO underscores that pilotage areas require highly specialized local knowledge and experience of various specific port areas and waterways. The IMO had earlier highlighted that it does not intend to be involved with the member States’ pilotage systems (IMO 2003). As early as 1968, it recommended that States organize pilotage services in areas where they enhance navigational safety more effectively than other measures. Chapter V of SOLAS (see Regulation 23) notes that vessels engaged on voyages during which pilots may be employed are required to have pilot transfer arrangements to ensure the safety of pilots. In line with SOLAS, there is an obligation for State parties to establish various maritime safety services, including aids to navigation, hydrographic, meteorological, search and rescue, and vessel traffic services. However, pilotage services are not specifically mentioned among such mandatory services. Ehlers opines that this likely stems from the absence of a perceived need for international regulation of pilotage services to date (Ehlers Reference Ehlers2024, 4). Although the IMO, thus far rightly, avoided regulating pilotage issues comprehensively because of strong reference to varying local conditions, this may need to change, in part, in the era of MASS.

1.6.3 Compulsory Pilotage

A “compulsory” pilot is one required by national laws. Conversely, a “voluntary” pilot is one whom a ship owner chooses to employ without any legal obligation (Force Reference Force2004, 149). Pursuant to the Convention and Statute on the International Régime of Maritime Ports (see Article 11), State parties have the authority to administer pilotage, including the establishment of compulsory pilotage. Given the sovereignty exercised by coastal States over their internal waters and ports, there are generally no limitations under international law on the imposition of compulsory pilotage in these areas (Ehlers Reference Ehlers2024, 9–10).

Yet, unlike the authority to designate sea lanes or traffic separation schemes, UNCLOS does not expressly specify the procedures to establish compulsory pilotage in coastal waters. Thus, the rules of the reference system also do not point out to the IMO. Moreover, State practice is also not clear in this area. Nevertheless, a few examples show the possible competence of coastal States to implement quasi-compulsory pilotage within their territorial seas, as seen, for example, in the Strait of Messina, the Great Barrier Reef, and around Svalbard Island. The adoption of such pilotage systems depends on the unique characteristics of each area, including the reliability of the system, the availability of qualified pilots, and the cost of services, and, more importantly, the nonhampering of the innocent passage (Solski Reference Solski2021, 411–414).

For pilotage services offered within internal waters, including port areas, there is generally no issue, as the coastal State exercises unrestricted sovereignty therein. Nevertheless, beyond internal waters, the legality of establishing pilotage services depends on whether such services impair the existing rights of navigation in the respective maritime zones. This consideration is crucial in maintaining the balance between enhancing safety through pilotage and upholding the principle of freedom of navigation as prescribed by international law (Ehlers Reference Ehlers2024, 5–6). Notably, one should be cautious considering that Australian efforts to impose compulsory pilotage as a protective measure in the Particularly Sensitive Sea Area of the Torres Strait have faced strong opposition from flag States underscoring their transit passage rights under international law. The eventual compromise involved enforcing compulsory pilotage in the Torres Strait exclusively for vessels entering Australian ports (Kopela Reference Kopela2016, 101–102).

However, despite the limitations, Article 21(1)(a) and (f) of UNCLOS allows coastal States to implement regulations aimed at enhancing maritime safety and environmental protection. This framework arguably enables coastal States to mandate pilotage in these waters as a measure to ensure the safety of navigation and safeguard the marine environment in relation to RCS operations while still respecting the principle of innocent passage. However, any national regulations related to pilotage must not only pursue safety and environmental protection but also adhere strictly to established international norms. In light of this, the compulsory pilotage for MASS arguably would not be seen as an interference with the navigational passage rights. Therefore, compulsory pilotage, when implemented to enhance navigational safety and environmental protection, does not contravene Articles 24(1) and 211(4) and can be regarded as necessary and proportionate. Moreover, the compulsory pilotage in port approach waters beyond internal waters can be justified, especially when ships are bound to enter internal waters or ports, as coastal States can set conditions for entry to their ports based on Article 25(2). Indeed, this provision allows the coastal State to enforce regulations such as compulsory pilotage to prevent breaches of entry conditions into its waters (Ehlers Reference Ehlers2024, 9–13).

Arguably, the coastal States seem to have the discretion to mandate compulsory pilotage for RCS as a condition for port entry. For instance, while pilotage through the Turkish Straits remains optional during peace times for merchant vessels under the 1936 Montreux Convention (Articles 2 and 4),Footnote ¹⁸ Türkiye can impose obligatory pilotage services in the straits if there is an imminent threat of war (Article 6). Significantly, this situation differs for ships that are calling at a Turkish port within the straits area, where compulsory pilotage can be established as a port entry requirement. Pilotage services for RCS to alleviate the concerns of port States, and even of coastal States, should be established and elucidated under the IMO’s MASS Code to enhance the safety of navigation and environmental protection. Concurrently, the conditions under which States can mandate compulsory pilotage for MASS beyond internal waters need to be clarified to ensure consistent application and understanding. This may be contingent upon the consent of IMO member States, like existing regulations for ship routing and ship reporting services (Ehlers Reference Ehlers2024, 18–24).