The United Nations (UN) Protocol against the Smuggling of Migrants by Land, Sea and Air is the foremost international response to a phenomenon that has emerged as one of the most significant political, social, and criminal justice issues worldwide.1 Article 3(a) of the Protocol defines the term ‘smuggling of migrants’ to mean ‘the procurement, in order to obtain, directly or indirectly, a financial or other material benefit, of the illegal entry of a person into a State Party of which the person is not a national or a permanent resident.’

Since its inception, the Smuggling of Migrants Protocol has gained considerable worldwide. Within two years of opening the Protocol for signature in December 2000, 112 States from around the world signed it. The Protocol entered into force on 28 January 2004 following ratification by 40 States, as required by Article 22(1) of the Protocol. The Protocol has found much popularity among Eastern European, Western States, and among Latin American and Caribbean States. Uptake by countries of the Asia Pacific Region, on the other hand, has been particularly slow and by the end of 2014, the majority of States in the Asia Pacific region had not yet ratified the Protocol. Considerable ratification throughout Africa also came swiftly, although there remain a significant number of African States that have yet to ratify.

Background and Development

Negotiations for the elaboration of an international treaty to combat the smuggling of migrants began in the 1990s amidst growing concerns about irregular and uncontrolled migration in the post Cold-War era.

The UN General Assembly first addressed the issue of migrant smuggling in Resolution 48/102 of 20 December 1993, entitled ‘prevention of the smuggling of aliens’. To further advance consultations in this field, the Resolution requested the UN Commission on Crime Prevention and Criminal Justice (CCPCJ) to give special attention to the issue of migrant smuggling at its third session, held in Vienna between 26 April and 6 May 1994. In discussing this issue, the Commission noted that ‘[a]lien smuggling was considered a matter of grave concern for many Governments’ and suggested that ‘[c]riminal legislation should be enacted and enforced to combat the abominable practice’.2 Between 1994 and 1997, the General Assembly, the CCPCJ, and the Economic and Social Council revisited the topic of migrant smuggling several times, thus paving the way for greater international cooperation in this field.

In mid-1997, the Government of Italy submitted a proposal for a draft convention to define and target the smuggling of migrants by sea to the International Maritime Organization (IMO).3 The primary concern of the Italian Government was about the heavy loss of life when crowded, unseaworthy smuggling vessels sank in the Mediterranean en route to Italy. A separate initiative by the Austrian Government pursued a similar goal. On 16 September 1997, Austria submitted a letter to the UN Secretary-General presenting a draft ‘International Convention against the Smuggling of Illegal Migrants’.4 Italy expressed its support of the Austrian proposal and the two governments agreed to combine their initiatives. This was achieved by including special measures relating to the smuggling of migrants by sea into the Austrian draft. The proposals by the Austrian and Italian governments also found strong support in various UN bodies and coincided with moves by the UN General Assembly to establish an open-ended intergovernmental Ad Hoc Committee for the Elaboration of a Convention against Transnational Organized Crime (AC.154).5

The combined Austrian and Italian proposal constitutes the main textual influence of the Smuggling of Migrants Protocol.6 Over the following two years, the Ad Hoc Committee developed the Convention against Transnational Organized Crime, along with three supplementing protocols, including the Protocol against the Smuggling of Migrants by Land, Sea, or Air. The Convention and Protocol were opened for signature on 15 December 2000. The Protocol entered into force on 28 January 2004.7

Outline and Obligations


The stated purpose of the Smuggling of Migrants Protocol is ‘to prevent and combat the smuggling of migrants, as well as to promote cooperation among States Parties to that end, while protecting the rights of smuggled migrants’.8 To achieve this purpose, the Protocol sets out a comprehensive framework to criminalise the smuggling of migrants, enable cross-border cooperation, and protect the rights of smuggled migrants.

The Smuggling of Migrants Protocol supplements the UN Convention against Transnational Organized Crime.9 This relationship between the Protocol and the Convention squarely places the phenomenon of migrant smuggling into the category of organised crime. Through the Convention, States Parties to the Protocol also gain access to a myriad of investigative, prosecutorial, and judicial tools to combat organised crime, including in cases that require international cooperation.


Upon signing the Protocol, States agree to make the smuggling of migrants and related conduct under Article 6(1) a criminal offence.10 Article 6(1) identifies three offences that must be established in domestic law, including: a smuggling of migrants offence in Article 6(1)(a); a document fraud offence in Article 6(1)(b); and an offence of enabling of illegal stay (or harbouring) in Article 6(1)(c). Article 6(2) also encourages States Parties to criminalise attempting, participating, organising, and directing any of the offences set out in Article 6(1)(a)–(c). Article 6(3) creates an obligation to incorporate ‘aggravating circumstances’ into the offences established pursuant to Article 6(1). The two aggravations specifically listed in Article 6(3) include ‘circumstances (a) that endanger, or are likely to endanger, the lives or safety of the migrants concerned; or (b) that entail inhuman or degrading treatment, including for exploitation, of such migrants.’ It is open to States Parties to legislate on other aggravating circumstances.

Article 5 of the Protocol stipulates the principle of non-criminalisation of smuggled migrants, stating that ‘migrants shall not become liable to criminal prosecution under this Protocol for the fact of having been the object of conduct set forth in Article 6 of this Protocol.’11

Smuggling of Migrants by Sea

The prevention and suppression of the smuggling of migrants by sea is specifically addressed in Articles 7–9. Article 7 requires that all States cooperate ‘to the fullest extent possible to prevent and suppress the smuggling of migrants by sea’. Article 8 sets out boarding powers at sea — including requesting permission to board and search the vessel of another State Party — as well as obligations, including the establishment of an authority to verify the legitimate registration of vessels. Article 9 is a safeguard clause creating a responsibility to protect the vessel and its passengers, and to reimburse a vessel damaged during a search.

International Cooperation

Several articles in the Protocol make provisions for international cooperation. Article 10 encourages States Parties to exchange information and Article 13 obliges States to verify the legitimacy of documents at the behest of another State. The Protocol also encourages States Parties to enhance border controls, document security, training of law enforcement and border officials, and the implementation of public information programmes.12 Articles 14(3) and 15(3) specify that States shall consider providing technical and financial assistance to other States.

Protecting the rights of smuggled migrants

Article 4 extends the scope of the Protocol to ‘the protection of the rights of persons who have been the object of [migrant smuggling]’.13 Under Article 9(1), States Parties are obliged to ‘ensure the safety and humane treatment of the persons on board’ suspected smuggling vessels. Article 16 sets out a number of ‘protection and assistance measures’ that afford smuggled migrants some basic guarantees of protection and aid. Article 19 contains a saving clause which obliges State Parties to give deference to the ‘other rights, obligations and responsibilities of States and individuals under international law,’ and to apply the Protocol in a way ‘that is not discriminatory to persons on the ground that they are the object of’ migrant smuggling. The Protocol also sets out a framework for receiving States for the repatriation of smuggled migrants.14

For further outlines, analyses, and critique of the Smuggling of Migrants Protocol, see:

  • Andreas Schloenhardt & Jessica E Dale, ‘Twelve years on: revisiting the UN Protocol against the Smuggling of Migrants by Land, Sea and Air’ (2012) 67 Zeitischrift für öffentliches Recht/Austrian Journal of Public Law 129–156;
  • Andreas Schloenhardt, ‘The UN Protocol against the Smuggling of Migrants by Land, Sea and Air (2000)’, in P Hauck & S Peterke (eds), International Law and Transnational Organized Crime, Oxford: Oxford University Press, 2015 (forthcoming)

Barriers to Ratification

Although the Smuggling of Migrants Protocol has found widespread adoption worldwide, many countries have not — or not yet — signed and ratified the Protocol. Many critics argue that the Protocol promotes the views of rich, developed destinations countries and offers little incentives for developing countries of origin to support the Protocol.

States that have not, or not yet, Parties to the Smuggling of Migrants Protocol may be reluctant to commit themselves to this body of law because they lack the resources, capacity, or the political will to sign a treaty that they consider unnecessarily burdensome or conflicting with national interests.15 The smuggling of migrants is a highly complex international problem without a single, standardised, or low-cost solution. If States lack effective governance and institutions to properly implement the Protocol, they are arguably less likely to undertake legal obligations in the first place. Civil conflict and unrest in many countries are further obstacles to the accession to and ratification of international instruments, including the Smuggling of Migrants Protocol. In this context, it should be noted that the lack of any rule of law that occurs during and after an armed conflict in a country or region might expose the population to a particularly high risk of irregular migration and of falling prey to the promises made by migrant smugglers.

Proper implementation of the Protocol’s criminalisation, cooperation, and protection provisions requires a very substantial financial and material commitment. For this reason, lack of such resources may provide an additional barrier to ratification. The perceived lack of incentives, the view that enough is already done through national laws or non-binding regional initiatives, and a general reluctance to accept binding obligations on issues that traditionally have been matters of national concern are other reasons why some countries may choose not sign the Protocol.

Research conducted by the UQ Migrant Smuggling Working Group in 2014–15 examines the levels of and barriers to ratification of the Protocol in order to shed light into the reasons why some countries hesitate or choose not to sign the Smuggling of Migrants Protocol. The research findings identify the main obstacles and develop ideas and recommendations to enable wider ratification. The full findings have been published in:

  • Andreas Schloenhardt & Hamish Macdonald, ‘Barriers to Ratification of the United Nations Protocol against the Smuggling of Migrants’ (2016) 1 Asian Journal of International Law