Drug Trafficking

Criminal Flows No Comments


The United Nations’ definition of drug trafficking covers the entire drugs production and dissemination chain, including ‘cultivation, manufacture, distribution, and sales of substances which are subject to drug prohibition laws’.1 This article is primarily interested in distribution, focusing on the movement of drugs by maritime routes. It focuses on heroin, cocaine, cannabis, and Amphetamine-Type-Substances (ATS) due to their prevalence.

PACIFIC OCEAN (June 2, 2020) The Arleigh Burke-class guided-missile destroyer USS Preble (DDG 88) with embarked U.S. Coast Guard (USCG) Law Enforcement Detachment (LEDET) team conducts enhanced counter narcotics operations June 2. The Preble and embarked LEDET recovered over 2,000 kilograms of suspected cocaine By U.S. Pacific Fleet (Attribution-NonCommercial 2.0 Generic (CC BY-NC 2.0))


The maritime domain

While patterns of drug trafficking differ depending on the type of drug and local context, maritime routes are significant in many drug trafficking activities. An estimated 90 per cent of all cocaine produced, for example, is transported via maritime routes.2 Drug trafficking to Europe from South America, West Africa, and North Africa mostly takes place across the maritime domain.3 The extent to which maritime trafficking constitutes a popular route can also be seen in seizure numbers. Most seizures happen on land, but the largest in value are from maritime sources.4

There have been three general trends that contribute to the increasing use of maritime routes for drug smuggling.

First, is the growth of maritime infrastructure across the globe which facilitates both licit trade and illicit trafficking. Studies on China’s Belt and Road Initiative, for example, suggest that infrastructure development in regions such as Southeast Asia will open access to illicit markets and are already attracting the attention of criminals.5 More generally, there is a strong body of evidence pointing to the relationship between crime and development, especially if infrastructure is prioritised in countries with weak governance and limited regulatory capacity.6 As the volume of trade increases, it facilitates easier passage for illicit goods because larger volumes of containers make detection more costly. Port authorities in Africa and Europe have an average capacity to physically screen fewer than 2% of containers moving through their ports.7

Second, the drug trade is a site of mutual learning between law enforcement and traffickers, which leads to an adaptability and dynamism in the means and routes by which drugs are moved. This reciprocal influence between evasion and interdiction means that maritime routes are continuously evolving.8 For example, the preferred entry ports for drug traffickers often change, with shipments moving from port to port depending on perceived ease of access.9 There is evidence that switching between interlinked hubs builds redundancies into the drugs trafficking trade, and enables traffickers to use the maritime sphere to adapt to law enforcement developments.10

Finally, the COVID-19 pandemic intensified the use of maritime routes by drug traffickers.11 With border closures creating difficulties moving consignments across land borders and much of the global air industry grounded, maritime routes emerged as a preferred alternative with record seizures were recorded in several countries,12

Types of drugs

All forms of drug can be trafficked by the sea, but four types are of particular note. These are cannabis, cocaine, heroin, and amphetamine-type stimulants (ATS). The different characteristics of these drugs impact on the means through which they are trafficked. Cocaine, heroin and synthetics for example have high price to weight ratios meaning that smaller shipments can still be very profitable.13 Cannabis trafficking needs to be done in bulk for it to be financially viable.14


These differences mean maritime trafficking can take many different forms depending on the drug. Some are trafficked by concealment in cargo and containers, shipped alongside licit goods.15 Drug traffickers may pack and collect consignments in containers directly, or tamper with llict shipments to conceal drugs within them (often unbeknownst to the container’s owner). 16 Quite often, drugs are sent from port to port to conceal the fact the containers came from high-risk countries.17

Other drugs are shipped in smaller vessels, including recreational sailing vessels,18 speedboats,19 fishing vessels,20 and dhows.21

The availability of sailing vessels, for example, means that they are commonly used for the movement of cocaine between the Caribbean and Europe.22 Sometimes, these may directly traffic drugs, but at other times they may be supplied en route by so called ‘motherships’, that is larger transshipment vessels that store drugs remain off the coast away from law enforcement.23 Drugs can then be collected by the smaller vessels with local crews. Drugs may not be carried onboard the mothership directly but may also be dragged underwater in steel ‘torpedoes’ or left in a spot with a buoy for pick up by another vessel.24

Some drug traffickers use submersible trafficking methods. Practices include hiding drugs below the waterline of large vessels, either attached to the ship’s hull with screws or magnets,25 or hidden inside ship’s spaces that can only be reached from underneath.26.

There has also been an increase in the use of low profile vessels (LPVs), self-propelled semisubmersibles (SPSS), and even submarines to traffic drugs.27 These are all vessels that are in someway submersed to avoid detection. Currently localised to South America, these vessels are often referred to as Narcosubmarines, and are evidence of significant innovation and investment by drugs traffickers.28 They are often discarded after completing their one-trip journey. This practices is financially viable because of the large cargos they can carry, in some cases up to ten tons of cocaine.29


The type of drug drug also influences the route used for trafficking.

For example, cannabis can be cultivated in many different places, and continues to be the most widely cultivated illicit crop worldwide.30 Since 2010, the illicit cultivation of cannabis has been reported, directly or indirectly, by 151 countries across all regions.31 As a result, the routes are often across short distances because markets and suppliers tend to be closer. An example is cannabis resin trafficked across the Mediterranean from Morocco into Europe.32

Synthetic drugs such as methamphetamine and ketamine have a high weight to price ratio and can be produced in countries with weak law enforcement oversight or with nearby consumer access.33 Trafficking routes also tend to be quite short. An example is the Western Maritime Route from Myanmar along the coast of Southeast Asia, for distribution to nearby countries. 34

Cocaine is only produced in eight countries, and is therefore trafficked across borders more regularly and at greater distances.35 Significant routes include the Eastern Pacific Route from Colombia to Mexico and the United States,36 and the Western Atlantic Route into the Caribbean then across to Europe.37 Cocaine is also trafficked to West Africa, and then on to Europe.38

West Africa has emerged as a major trafficking hub, with traffickers having bases in at least 11 of 16 West African countries due to the weakness of law enforcement and state incapacity to deal with the issue.39 The epicentre of the cocaine market in Europe has also shifted northwards. The UNODC Notes: ‘the increased use of containerized shipments relying on the high-volume ports of Antwerp, Rotterdam and Hamburg has consolidated the role of the Netherlands as a staging point and led to continental Europe’s North Sea coast overtaking the Iberian peninsula as the primary point of entry for cocaine reaching Europe‘.40

Heroin also has a low geographic range of production, with direct and indirect evidence of the illicit cultivation of opium poppy observed in 55 countries.41 Many of these locations are inland, such as Afghanistan, or share a land border with their main consumer, such as Mexico and the USA. Maritime routes include the West Indian Ocean, where heroin is trafficked from Pakistan to East Africa and eventually on to Europe.42 In 2019, India reported a strong increase (157 per cent) in heroin shipments from South-West Asia by sea.43

Other areas such as the Pacific Islands are emerging as increasingly significant in the international drugs trade, due to their porous maritime borders and location between producing countries in South America and Asia, and markets such as Australia.44


Much research on drug trafficking analyses criminal networks. Drug trafficking tends to be highly organised, even when conducted on a smaller scale.45

There has been a significant shift from producers-as-traffickers to independent traffickers who are ‘subcontracted’ due to their transport expertise.46 According to UN Office on Drugs and Crime’s (UNODC) Report of the High-Level Panel on Threats Challenges and Changes, organised crime is ‘increasingly operating through fluid networks rather than more formal hierarchies. This form of organisation provides criminals with diversity, flexibility, low visibility, and longevity’.47

Trafficking requires having people at the port of origin to assemble consignments and conceal drugs, and people to bribe customs officers if required. At the port of destination, people are needed to receive the container, unpack the drugs, and prepare them for onward transportation to their final destination. Likewise, organising large consignments along a route requires ‘financial resources, good logistics and sufficient capital reserves and/or sufficient profit margins to be able to absorb losses should drug consignments be intercepted’.48 These requirements have created a fluid and diverse trafficking network, whereby different criminal nodes will align for a particular trafficking activity, and then disperse and create a new network for the next shipment.49 Anna Sergi argues that this method requires complex strategic and logistical flexibility, which implies the coordination of efforts across loosely tied individuals accomplishing specific tasks. Importers are not always tied to distribution.50

While trafficking is not always centralized in the hands of one major ‘kingpin’, it is still a highly organized practice. Instead of competition arising from diversification, there is instead evidence of increasing collaboration between groups and the development of a more efficient supply chain. Some evidence suggests that such collaborations can result from kin ties or patterns of joint working which facilitate trust,51 but the primary explanation is that it results from an economic motivation rooted in the desire for efficiency.52

Some research suggests that these decentralised drug trafficking methods are more adaptable, with shifts in routes taking place quickly due to the specialised nature of the different nodes in the supply chain.53 Consequently, even smaller scale trafficking will in some cases be undertaken by the same nodes of actors as large-scale container trafficking for the sake of diversification.54 Smaller scale trafficking does not necessarily mean lesser degrees of organisation or criminality.

Due to the disruption drug trafficking can cause (see impacts), it is often seen as a significant security issue. It is also securitised on the basis that these networks can have links to terrorist organisations, insurgencies,55 or because the criminal groups concerned use violence on a large scale.56 Drug trafficking is one of the most common forms of criminality used by violent extremist organisations and terrorist groups to fund their activities.57


As with most forms of illicit activity, it is difficult to measure the scope of drug trafficking with any certainty. One approach is to analyse drug use and supply. For example, the UNODC’s annual drug report of 2018 estimates that 269 million (range: 166–373 million) people had used an illicit drug at least once in the previous year, equivalent to 5.4 per cent of the global population aged 15–64 58.

In order to assess supply, the UNDOC looks at hectares under cultivation.59 For example, and following a decline in the area under illicit opium poppy cultivation from a peak in 2017, global opium poppy cultivation rebounded in 2020, rising by 24 per cent compared with the previous year, to reach 295,000 ha. The global area under coca bush cultivation declined by 45 per cent over the period 2000–2013, before more than doubling over the period 2013–2018 to 245,000 hectares.

By analysing the markets and supply it is possible to see that overall scope of drug use and production is high, with an estimated global market value of 500 billion US dollars.60

Another measure is to look at seizures and arrest data. The UNODC publishes data on global seizures and year on year changes to analyse trends for example.61 It estimates that at current levels, world heroin consumption (340 tons) and seizures represent an annual flow of 430-450 tons of heroin into the global heroin market (with the extra being seized).62 However, these seizure data may say more about the extent to which police engage in certain types of activities and allocate resources than they do about the overall scope.

Some studies analyse trafficking through quantitative analysis of all three indicators. Atkinson et. al.63 for example analyses production levels, demand, and seizures to estimate how many vessels are smuggling drugs at any one time from South America to the USA. Their research suggests around 57 maritime drug shipments took place on this route each month over the period studied.



Drug trafficking can cause severe health problems.[/efn_note]Chen & Lin 2009; Degenhardt & Hall 2012; Rehm et al. 2006; UNODC n.d.[/efn_note] The burden of disease attributable to the use of drugs is measured by deaths and years of ‘healthy’ life lost.64 According to one study in 2019, an estimated 494,000 deaths and 30.9 million years of “healthy” life lost as a result of premature death and disability were attributable to the use of drugs.65

Social Instability

In some cases, drug trafficking can cause instability on a national level. In production countries, drug traffickers undermine governance and there have been cases of significant drug-related violence, including the assassination of politicians and battles between drug producers and national militaries over the control of cultivation areas.66 Drug money has funded insurgencies, which continue to sustain conflict. Examples can be found in Colombia and Myanmar, where insurgencies are heavily reliant on the drug trade.67 The influx of drug money may create a form of so-called ‘Dutch-disease’ whereby other forms of economic activity become unviable, creating a reliance on drug producers.68 Similar instability effects can sometimes also be seen in transit countries.69


In demand countries, economic burdens are primarily felt at a national level. This results from the need for increased healthcare due to the negative health implications and the cost of law enforcement to combat the drug trade.70

Linkages & Synergies

Drug trafficking is often linked to to other forms of crime, including violence, corruption, and theft.

In the maritime sector, there are also strongly evidenced links to IUU fishing activities.71 Interdiction records suggest that the global trade in illicit drugs often takes place through fishing vessels. While not all of these vessels engage in IUU fishing, there is evidence that IUU fishers are more involved in drug trafficking due to their experience in avoiding detection.72

This also links drug trafficking with other forms of trafficking. Because brokers are often those chosen for their trafficking expertise, they may also move multiple other types of illicit goods too.73



Drug trafficking is internationally regulated by the Single Convention on Narcotic Drugs of 1961 (as amended in 1972),74 the Convention on Psychotropic Substances of 1971, and the United Nations Convention against Illicit Traffic in Narcotic Drugs and Psychotropic Substances of 1988 (also known as the Vienna convention).75 Following these treaties, the Commission on Narcotic Drugs and the International Narcotics Control Board were established. These regulations, plus the UN Convention against Transnational Organised Crime (UNTOC),76 delineate state responsibilities to combat drug trafficking.

UNTOC and the 1988 Vienna Convention both authorise jurisdiction where offences are ‘committed on board a vessel that is flying the flag of that State Party’, committed by a national (or resident), or where the offence involves ‘participation in an organized criminal group’ outside territorial jurisdiction, but where the offence is a ‘serious crime’.77 This has given states a strong mandate to deal with drug trafficking by sea.

The creation of the International Maritime Organization’s International Ship and Port Facility Security Code (ISPS) in 2002 and its update in July 2014 was enacted to standardise and bolster current security procedures, particularly at ports.78 Divided into two sections, the ISPS code contains detailed security-related requirements for governments, port authorities and shipping companies in mandatory Part A, and a series of guidelines on how to meet those requirements in a non-mandatory Part B.

International cooperation against drug trafficking takes many forms. Collaborative initiatives include joint maritime patrols that focus on interdiction,79 joint health interventions to lessen drug use and dependency,80 and joint operations against cultivation areas.81

International capacity building activities aimed at strengthening the (maritime) law enforcement capabilities of partner states are commonly delivered by actors including Interpol,82 the UNODC,83 and the IMO.84

There are also various measures aimed at information sharing between stakeholders. An example is the Container Control Programme, a joint initiative of the UNODC and World Customs Organization.85 The programme has increased security capacity and built international cooperation networks in both Latin American and European ports, and has directly contributed to an increase in seizures as well as operations against traffickers.86

Finally, organisations such as the International Chamber of Shipping (ICS) have published best practice guides for stakeholders potentially impacted by the maritime drugs trade. An example is the ICS’s Drug Trafficking and Drug Abuse On Board Ship: Guidelines for Owners and Masters on Preparation, Prevention, Protection and Response document.87

Even so, such efforts face considerable obstacles and limitations, including the difficulty of identifying illicit vessels and their movements at sea, the adaptability of drug traffickers and their methods, and challenges of law enforcement capacity and coordination in the maritime and port sectors.  

List of references

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