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Introduction

Adopting a convention, Entry into force, Accession, Amendment, Enforcement, Tacit acceptance procedure


​Introduction
The industrial revolution of the eighteenth and nineteenth centuries and the upsurge in international commerce which followed resulted in the adoption of a number of international treaties related to shipping, including safety.  The subjects covered included tonnage measurement, the prevention of collisions, signalling and others.

By the end of the nineteenth century suggestions had even been made for the creation of a permanent international maritime body to deal with these and future measures.  The plan was not put into effect, but international co-operation continued in the twentieth century, with the adoption of still more internationally-developed treaties. (more)

Adopting a convention
This is the part of the process with which IMO as an Organization is most closely involved.  IMO has six main bodies concerned with the adoption or implementation of conventions.  The Assembly and Council are the main organs, and the committees involved are the Maritime Safety Committee, Marine Environment Protection Committee, Legal Committee and the Facilitation Committee.  Developments in shipping and other related industries are discussed by Member States in these bodies, and the need for a new convention or amendments to existing conventions can be raised in any of them.


Entry into force
The adoption of a convention marks the conclusion of only the first stage of a long process.  Before the convention comes into force - that is, before it becomes binding upon Governments which have ratified it - it has to be accepted formally by individual Governments.


Signature, ratification, acceptance, approval and accession
The terms signature, ratification, acceptance, approval and accession refer to some of the methods by which a State can express its consent to be bound by a treaty.
 
Signature
Consent may be expressed by signature where:
  • the treaty provides that signature shall have that effect;
  • it is otherwise established that the negotiating States were agreed that signature should have that effect;
  • the intention of the State to give that effect to signature appears from the full powers of its representatives or was expressed during the negotiations (Vienna Convention on the Law of Treaties, 1969, Article 12.1).
 
A State may also sign a treaty "subject to ratification, acceptance or approval".  In such a situation, signature does not signify the consent of a State to be bound by the treaty, although it does oblige the State to refrain from acts which would defeat the object and purpose of the treaty until such time as it has made its intention clear not to become a party to the treaty (Vienna Convention on the Law of Treaties, Article 18(a)).
 
Signature subject to ratification, acceptance or approval
Most multilateral treaties contain a clause providing that a State may express its consent to be bound by the instrument by signature subject to ratification.
In such a situation, signature alone will not suffice to bind the State, but must be followed up by the deposit of an instrument of ratification with the depositary of the treaty.
 
This option of expressing consent to be bound by signature subject to ratification, acceptance or approval originated in an era when international communications were not instantaneous, as they are today.
 
It was a means of ensuring that a State representative did not exceed their powers or instructions with regard to the making of a particular treaty. The words "acceptance" and "approval" basically mean the same as ratification, but they are less formal and non-technical and might be preferred by some States which might have constitutional difficulties with the term ratification.
Many States nowadays choose this option, especially in relation to multinational treaties, as it provides them with an opportunity to ensure that any necessary legislation is enacted and other constitutional requirements fulfilled before entering into treaty commitments.
 
The terms for consent to be expressed by signature subject to acceptance or approval are very similar to ratification in their effect.  This is borne out by Article 14.2 of the Vienna Convention on the Law of Treaties which provides that "the consent of a State to be bound by a treaty is expressed by acceptance or approval under conditions similar to those which apply to ratification."

Accession
Most multinational treaties are open for signature for a specified period of time. Accession is the method used by a State to become a party to a treaty which it did not sign whilst the treaty was open for signature.
Technically, accession requires the State in question to deposit an instrument of accession with the depositary. Article 15 of the Vienna Convention on the Law of Treaties provides that consent by accession is possible where the treaty so provides, or where it is otherwise established that the negotiating States were agreed or subsequently agreed that consent by accession could occur.

Amendment
Technology and techniques in the shipping industry change very rapidly these days. As a result, not only are new conventions required but existing ones need to be kept up to date. For example, the International Convention for the Safety of Life at Sea (SOLAS), 1960 was amended six times after it entered into force in 1965 - in 1966, 1967, 1968, 1969, 1971 and 1973. In 1974 a completely new convention was adopted incorporating all these amendments (and other minor changes) and has itself been modified on numerous occasions.
 
In early conventions, amendments came into force only after a percentage of Contracting States, usually two thirds, had accepted them. This normally meant that more acceptances were required to amend a convention than were originally required to bring it into force in the first place, especially where the number of States which are Parties to a convention is very large.
 
This percentage requirement in practice led to long delays in bringing amendments into force. To remedy the situation a new amendment procedure was devised in IMO. This procedure has been used in the case of conventions such as the Convention on the International Regulations for Preventing Collisions at Sea, 1972, the International Convention for the Prevention of Pollution from Ships, 1973 and SOLAS 1974, all of which incorporate a procedure involving the "tacit acceptance" of amendments by States.
 
Instead of requiring that an amendment shall enter into force after being accepted by, for example, two thirds of the Parties, the “tacit acceptance” procedure provides that an amendment shall enter into force at a particular time unless before that date, objections to the amendment are received from a specified number of Parties.
 
In the case of the 1974 SOLAS Convention, an amendment to most of the Annexes (which constitute the technical parts of the Convention) is `deemed to have been accepted at the end of two years from the date on which it is communicated to Contracting Governments...' unless the amendment is objected to by more than one third of Contracting Governments, or Contracting Governments owning not less than 50 per cent of the world's gross merchant tonnage. This period may be varied by the Maritime Safety Committee with a minimum limit of one year.
 
As was expected the "tacit acceptance" procedure has greatly speeded up the amendment process.  Amendments enter into force within 18 to 24 months, generally  Compared to this, none of the amendments adopted to the 1960 SOLAS Convention between 1966 and 1973 received sufficient acceptances to satisfy the requirements for entry into force.

Enforcement
The enforcement of IMO conventions depends upon the Governments of Member Parties.
 
Contracting Governments enforce the provisions of IMO conventions as far as their own ships are concerned and also set the penalties for infringements, where these are applicable.
 
They may also have certain limited powers in respect of the ships of other Governments.
 
In some conventions, certificates are required to be carried on board ship to show that they have been inspected and have met the required standards.  These certificates are normally accepted as proof by authorities from other States that the vessel concerned has reached the required standard, but in some cases further action can be taken.
 
The 1974 SOLAS Convention, for example, states that "the officer carrying out the control shall take such steps as will ensure that the ship shall not sail until it can proceed to sea without danger to the passengers or the crew".
This can be done if "there are clear grounds for believing that the condition of the ship and its equipment does not correspond substantially with the particulars of that certificate".
 
An inspection of this nature would, of course, take place within the jurisdiction of the port State.  But when an offence occurs in international waters the responsibility for imposing a penalty rests with the flag State.
Should an offence occur within the jurisdiction of another State, however, that State can either cause proceedings to be taken in accordance with its own law or give details of the offence to the flag State so that the latter can take appropriate action.
 
Under the terms of the 1969 Convention Relating to Intervention on the High Seas, Contracting States are empowered to act against ships of other countries which have been involved in an accident or have been damaged on the high seas if there is a grave risk of oil pollution occurring as a result.
The way in which these powers may be used are very carefully defined, and in most conventions the flag State is primarily responsible for enforcing conventions as far as its own ships and their personnel are concerned.
The Organization itself has no powers to enforce conventions.
 
However, IMO has been given the authority to vet the training, examination and certification procedures of Contracting Parties to the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW), 1978. This was one of the most important changes made in the 1995 amendments to the Convention which entered into force on 1 February 1997. Governments have to provide relevant information to IMO's Maritime Safety Committee which will judge whether or not the country concerned meets the requirements of the Convention.
 
Relationship between Conventions and interpretation
Some subjects are covered by more than one Treaty. The question then arises which one prevails. The Vienna Convention on the Law of Treaties provides in Article 30 for rules regarding the relationship between successive treaties relating to the same subject-matter. Answers to questions regarding the interpretation of Treaties can be found in Articles 31, 32 and 33 of the Vienna Convention on the Law of Treaties. A Treaty shall be interpreted in good faith in accordance with the ordinary meaning to be given to the terms of the treaty in their context and in the light of its object and purpose. When a Treaty has been authenticated in two or more languages, the text is equally authoritative in each language, unless the treaty provides or the parties agree that, in case of divergence, a particular text shall prevail.
 
Uniform law and conflict of law rules
A substantive part of maritime law has been made uniform in international Treaties. However, not every State is Party to all Conventions and the existing Conventions do not always cover all questions regarding a specific subject. In those cases conflict of law rules are necessary to decide which national law applies. These conflict of law rules can either be found in a Treaty or, in most cases, in national law.

IMO conventions
The majority of conventions adopted under the auspices of IMO or for which the Organization is otherwise responsible, fall into three main categories.
The first group is concerned with maritime safety; the second with the prevention of marine pollution; and the third with liability and compensation, especially in relation to damage caused by pollution.  Outside these major groupings are a number of other conventions dealing with facilitation, tonnage measurement, unlawful acts against shipping and salvage, etc.

Tacit acceptance procedure
The amendment procedures contained in the first Conventions to be developed under the auspices of IMO were so slow that some amendments adopted have never entered into force. This changed with the introduction of the "tacit acceptance" procedure.
 
Tacit acceptance is now incorporated into most of IMO's technical Conventions. It facilitates the quick and simple modification of Conventions to keep pace with the rapidly-evolving technology in the shipping world. Without tacit acceptance, it would have proved impossible to keep Conventions up to date and IMO's role as the international forum for technical issues involving shipping would have been placed in jeopardy.
 
In the spring of 1968, IMO - then still called IMCO, the Inter-Governmental Maritime Consultative Organization - celebrated the 20th anniversary of the adoption of the IMO Convention. It should have been an occasion for some congratulations. But all was not well. Many of the Organization's Member States were not happy with the progress that had been made so far.
 
Many were concerned about the Organization's structure and its ability to respond to the changes taking place in shipping. In March, 1967, the oil tanker Torrey Canyon had gone aground off the coast of England, resulting in what was then the world's biggest oil spill. IMO was called upon to take action to combat oil pollution and to deal with the legal issues that arose. But would it be able to do so?
 
The general disquiet was summed up by Canada in a paper submitted to the 20th session of the IMO Council in May 1968. It stated that "the anticipations of twenty years ago have not been fulfilled" and went on to complain of the effort required by Member States in attending meetings and dealing with the technical problems raised by IMO. The paper was discussed by the Council which agreed to establish a working group to prepare a draft statement of the objectives of IMO and an inventory of further objectives which the Organization could usefully fulfil in the field of international maritime transport.
 
In November 1968 the working group reported back to the Council. It outlined a list of activities, far broader than the programmes undertaken by IMO so far. This was approved by the Council, which also agreed that IMO needed to improve its working methods.
 
The working group was asked to report to the Council again at its 22nd session in May 1969.This time it put forward a number of proposals for improving IMO's working methods, the most important of which concerned the procedures for amending the various Conventions that had been adopted under IMO's auspices.
 
The problem facing IMO was that most of its Conventions could only be updated by means of the "classical" amendment procedure. Amendments to the 1960 SOLAS Convention, for example, would enter into force "twelve months after the date on which the amendment is accepted by two-thirds of the Contracting Governments including two-thirds of the Governments represented on the Maritime Safety Committee. This did not seem to be a difficult target when the Convention was adopted, because to enter into force the Convention had to be accepted by only 15 countries, seven of which had fleets consisting of at least 1 million gross tons of merchant shipping.
 
But by the late 1960s the number of Parties to SOLAS had reached 80 and the total was rising all the time as new countries emerged and began to develop their shipping activities. As the number of Parties rose, so did the total required to amend the Convention. It was like trying to climb a mountain that was always growing higher and the problem was made worse by the fact that Governments took far longer to accept amendments than they did to ratify the parent Convention.
 
The Council approved the working group's proposal that "it would be a useful first step to undertake a comparative study of the conventions for which IMO is depositary and similar instruments for which other Members of the United Nations family are responsible." This proposal was endorsed by the 6th regular session of the IMO Assembly in October 1969 and the study itself was completed in time to be considered by the Assembly at its 7th session in 1971.
 
It examined the procedures of four other UN agencies: the International Civil Aviation Organization (ICAO), the International Telecommunications Union (ITU), the World Meteorological Organization (WMO) and the World Health Organization (WHO).
 
It showed that all of these organizations were able to amend technical and other regulations. These amendments became binding on Member States without a further act of ratification or acceptance being required.
On the other hand, IMO had no authority to adopt, let alone amend conventions. Its mandate allowed it only to "provide for the drafting of conventions, agreements or other instruments and to recommend these to Governments and to intergovernmental organizations and to convene such conferences as may be necessary." Article 2 of the IMO Convention specifically stated that IMO's functions were to be "consultative and advisory".
 
The Organization could arrange a conference - but it was up to the conference to decide whether the Convention under discussion should or should not be adopted and to decide how it should be amended. The study concluded that "any attempt to bring IMO procedure and practice into line with the other organizations would, therefore, entail a change either in the constitutional and institutional structure of the Organization itself or in the procedure and practice of the diplomatic conferences which adopt the conventions of IMO.
 
The first might involve an amendment to the IMO Convention itself. The second might require that diplomatic conferences convened by IMO should grant greater power to the organs of IMO in regard to the review and revision of the instruments.
 
The study was discussed at length by the Assembly. Canada pointed out that the amendments adopted to the 1960 SOLAS Convention in 1966, 1967, 1968 and 1969 had failed to enter into force and this "sufficed to show that IMO would henceforth have to tackle serious institutional problems." A note submitted to the conference by Canada stated that "unless the international maritime community is sufficiently responsive to these changed circumstances, States will once again revert to the practice of unilaterally deciding what standards to apply to their own shipping and to foreign flag shipping visiting their ports."
 
The result was the adoption of resolution A.249(VII) which referred to the need for an amendment procedure "which is more in keeping with the development of technological advances and social needs and which will expedite the adoption of amendments." It called for the Legal Committee and Maritime Safety Committee to prepare draft proposals for consideration by the 8th Assembly.
 
A growing urgency was added by the fact that IMO was preparing a number of new conventions for adoption during the next few years. Conferences to consider a new Convention on the International Regulations for Preventing Collisions at Sea and an International Convention for Safe Containers were both scheduled for 1972, a major Convention dealing with the Prevention of Marine Pollution from Ships for 1973 and a conference to revise SOLAS was scheduled for 1976. All of these treaties required a new, easier amendment procedure than the traditional method.
 
The MSC discussed the amendment question at its 25th session in March 1972. A working group was formed to discuss the matter in detail and concluded that at current rates of acceptance the requisite "two-thirds" target needed to amend SOLAS 1960 "will not be achieved...for many years, possibly never." Moreover, any future amendments would almost certainly suffer the same fate. This would include any amendments intended to improve the amendment procedure itself.
 
The working group reported: "It follows that the only realistic way of bringing an improved amending procedure into effect within a reasonable period of time is to incorporate it into new or revised technical conventions.
A few weeks later, the Legal Committee held its 12th session. Among the documents prepared for the meeting was a report on discussions that had taken place at the MSC and a detailed paper prepared by the Secretariat. The paper analysed the entry into force and amendment processes of various IMO Conventions and referred to two possible methods that had been considered by the Assembly, for speeding up the amendment procedure. Alternative I was to revise each Convention so that greater authority for adopting amendments might be delegated to the appropriate IMO organs. Alternative II was to amend the IMO Convention itself and give IMO the power to amend Conventions.
 
The study then considered Alternative I in greater detail. The main reason why amendments took so long to enter into force was the time taken to gain acceptance by two-thirds of Contracting Governments. One way of reducing this period would be by "specifying a date ...of entry into force after adoption by the Assembly, unless that date of amendment is explicitly rejected by a certain number or percentage of Contracting Governments." The paper said that this procedure "has the advantage that all Contracting Governments would be able to advance the preparatory work for implementing the amended regulations and the industry would be in a position to plan accordingly."
 
The Committee established a working group to consider the subject and prepared a preliminary study based on its report, which again referred to the disadvantages of the classical amendment system. The study continued: "The remedy for this, which has proved to be workable in practice, in relation to a number of conventions, is what is known as the 'tacit' or 'passive' acceptance procedure. This means that the body which adopts the amendment at the same time fixes a time period within which contracting parties will have the opportunity to notify either their acceptance or their rejection of the amendment, or to remain silent on the subject. In case of silence, the amendment is considered to have been accepted by the party...".
 
The tacit acceptance idea immediately proved popular. The Council, at its meeting in May, decided that the next meeting of the Legal Committee should consist of technical as well as legal experts so that priority could be given to the amendment issue. The Committee was asked to give particular attention to tacit acceptance.
 
The idea was given non-governmental support by the International Chamber of Shipping, which had consultative status with IMO and submitted a paper stating that the lack of an effective amendment procedure created uncertainties and was detrimental to effective planning by the industry. The classical procedure had also encouraged some governments to introduce unilateral legislation that, however well intentioned, was "seriously disruptive to international shipping services." The paper said that if other Governments did the same " the disruption to international shipping and the world trade which it serves would become increasingly severe. Such unilateral action strikes at the purpose of IMO."
 
By the time the Legal Committee met for its 14th session in September 1972, there was general agreement that tacit acceptance offered the best way forward. Other ideas, such as amending the IMO Convention itself, had too many disadvantages and would take too long to introduce. There was some concern about what would happen if a large number of countries did reject an amendment and the Committee members agreed that tacit acceptance should apply only to the technical content of Conventions, which was often contained in annexes. The non-technical articles should continue to be subject to the classical (or "positive") acceptance procedure.
The Committee also generally agreed that alternative procedures for amending the technical provisions should be retained but it did not reach consensus on another issue: should amendments be prepared and adopted by an appropriate IMO body, such as the Maritime Safety Committee - or by Contracting Parties to the Convention concerned? This was an important point at the time, since many Contracting Parties to IMO Conventions were not yet Members of IMO itself and might object to treaties they had ratified being amended without them even being consulted.
 
This issue was still unsettled when the Conference on Revision of the International Regulations for Preventing Collisions at Sea opened in October 1972. The purpose of the conference was to update the Collision Regulations and to separate them from the SOLAS Convention (the existing regulations were annexed to SOLAS 1960).
 
The amendment procedure is contained in Article VI. Amendments to the Collision Regulations adopted by the MSC (by a two-thirds majority) have to be communicated to Contracting Parties and IMO Member States at least six months before being considered by the Assembly. If adopted by the Assembly (again by a two-thirds majority), the amendments enter into force on a date determined by the Assembly unless more than one third of Contracting Parties notify IMO of their objection. On entry into force, any amendment shall "for all Contracting Parties which have not objected to the amendment, replace and supersede any previous provision to which the amendment refers."
 
Less than two months later, on 2 December 1972 a conference held in Geneva adopted the International Convention for Safe Containers, Article X of which contains procedures for amending any part or parts of the Convention. The procedure is the traditional "positive" acceptance system, under which amendments enter into force twelve months after being adopted by two-thirds of Contracting Parties. However, Article XI contains a special procedure for amending the technical annexes which also incorporates tacit acceptance. The procedure is slightly different from that used in the Collision Regulations, one difference being that the amendments can be adopted by the MSC "to which all Contracting Parties shall have been invited to participate and vote." This answered the question of how to take into account the interests of Parties to Conventions that were not Member States of IMO.
 
The next Convention to be considered was the International Convention for the Prevention of Pollution from Ships (MARPOL), which was successfully adopted in May 1973. It, too, incorporated tacit acceptance procedures for amending the technical annexes. In the meantime, IMO was preparing for a new SOLAS convention. This was considered necessary because none of the amendments adopted to the 1960 version had entered into force and did not appear likely to do so in the near future. The 1966 Load Lines Convention also contained a classical amendment procedure and the intention was to combine the two instruments in a new Convention, which was scheduled to be considered in 1976.
 
The MSC discussed this proposal at its 26th session in October-November, but it was clear that this would be a daunting and time-consuming task. The combined instrument might be a good idea for the future - but the real priority was to get the amendments to SOLAS 1960 into force as quickly as possible and to make sure that future amendments would not be delayed. A working group was set up to consider the various alternatives, but opinion began to move in favour of a proposal by the United Kingdom that IMO should concentrate on an interim Convention designed to bring into force the amendments adopted since 1960. The new Convention, it was suggested, would consist of the 1960 text with the addition of a tacit acceptance amendment procedure and the addition of amendments that had already been adopted.
 
Another advantage, the United Kingdom pointed out, was that the conference called to adopt the revised Convention "might be held considerably earlier than 1976 since comparatively little preparation would be needed." The subject was discussed again at the MSC's 27th session in the spring of 1973 and, although some delegations wanted a more comprehensive revision, others felt that the workload would be so great that the conference would be seriously delayed. By a vote of 12 in favour and four abstentions, the Committee decided to call a conference with limited scope, as proposed by the United Kingdom.
 
On 21 October, 1974, the International Conference on Safety of Life at Sea opened in London and on 1 November a new SOLAS Convention was adopted, which incorporated the tacit acceptance procedure.
 
The tacit acceptance amendment procedure has now been incorporated into the majority of IMO's technical Conventions and has been extended to some other instruments as well. Its effectiveness can be seen most clearly in the case of SOLAS 1974, which has been amended on many occasions since then. In the process, the Convention's technical content has been almost completely re-written.