Concepts of modern slavery differ in terms of causal logics and the identification of challenges and problems. This leads to different solutions, strategies and delineations of responsibilities (Young 2006). International documents as well as scholarly approaches cover a broad range of modern forms of slavery. These legal and scholarly approaches build an essential basis for modelling the concept of modern slavery. This section provides an insight into current definitions and concepts, showing that they can be divided into two main approaches. Modern slavery is perceived as relation, on the one hand, and as structure, on the other. Note that this is an analytical, not a dichotomous distinction. It is based on a mutually constitutive relation between agency and structure. Agency and structure are mediated in that each constitutes and reproduces the other. At the same time, they remain analytically and logically distinct (Mende 2016, 49–62). In this mutually constitutive relation, slavery as structure supervenes slavery as relation. This means that change in the structure will initiate change in the relation, while this is not necessarily the case the other way round. The mediated understanding is able to prevent an interpretation that dichotomously detaches structure from agency—and modern slavery as relation from slavery as structure. However, by analytically distinguishing between the two, this section provides a pathway to the manifold approaches to modern slavery.
The term slavery is often used to denote historical forms of labour exploitation, e.g. the recruitment of indigenous people for labour in the colonies or the transatlantic slave trade (Dottridge 2005). In this historic context, the League of Nations prominently delineates slavery in its Slavery Convention from 1926. It defines slavery as “the status or condition of a person over whom any or all of the powers attaching to the right of ownership are exercised” (League of Nations 1926, Art 1.1). The Convention further includes a provision to prevent compulsory or forced labour (Art. 5), thereby addressing the widespread use of forced labour in colonised countries, even after the formal abolition of slavery (Ollus 2015, 103).
The Vienna Convention on the Law of Treaties states that, in addition to the socio-historical context within which international treaties are developed, “any subsequent agreement between the parties regarding the interpretation of the treaty or the application of its provision” (United Nations 1969, Art 31.3a) are to be taken into account. Thus, for the contemporary context, the Convention has to be examined in line with younger documents and with the United Nations human rights system. This includes the following reports and legal documents:
•1951 the report of the Ad-Hoc Committee of Experts on Slavery to the ECOSOC (Ad Hoc Committee on Slavery 1951),
•1953 the report by the Secretary General (United Nations Secretary General 1953),
•1956 the Supplementary Convention on the Abolition of Slavery, the Slave Trade, and Institutions and Practices Similar to Slavery (Supplementary Convention) (United Nations 1956),
•2000 the first Additional Protocol to Prevent, Suppress and Punish Trafficking in Persons, Especially Women and Children (Palermo Protocol) (United Nations 2000).
These reports and instruments confirm the “Slavery Convention as the authoritative source on what counts as slavery in law” and its applicability to modern slavery (Allain and Hickey 2012, 916). Moreover, they build the basis for national legislation regarding modern slavery, e.g. the United States Victims of Trafficking and Violence Protection Act (2000), the UK Modern Slavery Act (2015) and the Australia Modern Slavery Act (2018), elements of which are used as a guidance for global politics again. Adapted from this corpus of legal documents, together with scholarship from political science, economics and the social sciences, we differentiate modern slavery as interpersonal relation and modern slavery as structure as follows.
Modern Slavery as Relation
Concepts of modern slavery as an interpersonal relation mainly draw upon the legal notions in international law. This is because a legal perspective usually needs concrete action by a concrete agent that is linked to a certain incidence of modern slavery, both demanding for clear definitions.Footnote 3 In this context, slavery means the servile status of a person in relation to another person, characterised by “any or all of the powers attaching to the right of ownership” (United Nations 1956, Art. 7a). These powers are defined as absolute, executed over the person of servile status, serving the extraction of labour power, and they can be transferred (Allain 2013, 28). The most basic feature of ownership is possession, manifesting in claim-rights, liberties, powers and immunities (Allain and Hickey 2012, 925–30).
Since slavery is legally banned worldwide, ownership rights have been abolished. Nonetheless, slaveholders can still enforce de facto ownership without the de jure rights of ownership in a person. Slaveholders use de facto liberties, powers and immunities in order to exercise control over a person. They do so intentionally.Footnote 4 The modern reality of slavery translates into controlling a person “in such a way as to significantly deprive that person of his or her individual liberty, with the intent of exploitation through the use, management, purchase, sale, profit, transfer or disposal of that person” (Allain 2013; Research Network on the Legal Parameters of Slavery 2012, 2).
Thus, the first defining feature of modern slavery as relation is a de facto right to ownership as the execution of control of a person over another person. The relation is, second, of an involuntary nature, because third, it is marked by violence or its threat. The usage of coercion refers only to direct legal, political or other interpersonal means (ILO 2012). A situation in which a person is “forced into dangerous or difficult work by economic circumstances or other impersonal forces” (Craig et al. 2007, 13) is not covered by the approaches to slavery as relation (Galtung 1969). Fourth, this relation exists with the intention of exploitation. While structures and institutions can be exploitative as well, the intention of exploitation marks slavery as relation.
Very similar meanings can be found in international approaches to forced labour (Drubel 2019), and to trafficking, respectively. The ILO delineates forced or compulsory labour as “all work or service which is extracted from any person under the menace of any penalty and for which the said person has not offered himself voluntarily” (ILO 1930, Art. 2.1).Footnote 5 Physical or psychological coercion, e.g. physical violence, threats, deception, the involuntary entrance into the labour relation or the impossibility to leave the relationship, constitute coercive means:
While sometimes the means of coercion used by the exploiter(s) can be overt and observable (e.g., armed guards who prevent workers from leaving, or workers who are confined to locked premises), more often the coercion applied is more subtle and not immediately observable (e.g., confiscation of identity papers, or threats of denunciation to the authorities) (ILO 2012, 19).Footnote 6
Similar connections apply to the term trafficking (United Nations 2000, Art. 3a). At the beginning of the twentieth century, the term trafficking has been used to describe how women are moved from one country to another for the purpose of sex work or sexual exploitation. In 2000, the United Nations (UN) redefined the term as a practice of recruitment into modern slavery or forced labour including commercial sexual exploitation (Dottridge 2005, 707), or the “movement of people for the purpose of their exploitation” (Lerche 2007, 427).
While there are differences between modern slavery, forced labour and trafficking, they all amount to the four characteristics of slavery as relation: the de facto ownership of another person, the involuntary nature of the relation, the interpersonal use or the threat of violence and the intent of exploitation (Bales 2005, 4; Choi-Fitzpatrick 2012, 16; Craig et al. 2007, 12; Herzfeld 2002, 50; Moravcsik 1998, 174).
Modern Slavery as Structure
While interpersonal relations are a necessary condition for modern slavery, they may not be sufficient to understand and hence tackle modern slavery. Therefore, a body of scholarship focusses on the structures and institutions that constitute and enable slavery (Dottridge 2005; Miers 2000, 715). These approaches understand modern slavery as structure. They address first, impersonal forces and their embedding, second, its cross-level and cross-dimensional character to which actors can, third, contribute unintentionally.
First, the central criterion defining modern slavery as structure is impersonal force. This means that control is not only exercised via direct, interpersonal means of coercion or the threat thereof, but also by creating or using political, social, cultural, religious and economic contexts that make people more likely to be affected by modern slavery.
In this regard, the United States Victims of Trafficking and Violence Protection Act of 2000 diverges from the international approaches to slavery as relation, because it explicitly addresses structural violence and inequalities as causes for modern slavery. It states that “traffickers primarily target women and girls, who are disproportionately affected by poverty, the lack of access to education, chronic unemployment, discrimination, and the lack of economic opportunities in countries of origin” (United States of America 2000, Section 102.b.4). Similarly, social human rights perspectives are able to include and acknowledge structural inequalities (Mende 2019). This is because modern slavery is embedded in geographic, societal, political and historic structures (N. Taylor 2014, 133–34; Mezzadra and Neilson 2013, 105),Footnote 7 dependent on economic and socio-political context as well as their global ties (N. Taylor 2014, 133–34; Lebaron and Ayers 2013, 875; Peterson 2003, 45; Storper and Walker 1989, 154). Poverty and rural deprivation can make people more vulnerable to modern slavery. Likewise, political structures can tremendously enable modern slavery, such as repressive migration regimes which feed into informal labour, or anti-migration politics which even may expose victims of modern slavery to detainment, harassment and deportation (Brysk 2012, 73–85).Footnote 8
The enslavement of people from certain population groups is exacerbated in societies that are stratified along racist, sexist or other axes of structural inequality that are justified by caste, tradition, religion or post-colonial legacies. “Slave-traders use local beliefs and traditions to gain control over individuals […] where differences of race, ethnicity and religion still form the dividing lines between being slave and free” (Gold et al. 2015, 487, also cf. Crane 2013, 57; Bales 2016).
Second, the structures of inequality and impersonal forces interact between different dimensions and different spatial levels. They can exacerbate or contradict each other, with differing effects on modern slavery. The structures unfold cross-dimensional effects, e.g. when economic exploitation is enabled by cultural or religious vulnerabilities, by racism or sexism,Footnote 9 and they interact between global, regional, domestic and local levels, e.g. belief systems, economic rules and inequalities or environmental politics (Sylwester 2014, 453–58). Of particular importance is the dimension of political economy on the global level (Harvey 2006; Massey 1995; Scholte 2005; M. Taylor 2008a). It comprises varying rules concerning finance, trade, business and migration. It is constituted via business practices like foreign direct investments intending to organise production processes in global supply chains (Mosley 2011)Footnote 10 and by national policies that aim at, e.g. the creation of offshore centres or Export Processing Zones.Footnote 11 These operations and policies, their “heterogeneous constitution of global space” (Mezzadra and Neilson 2013, 97), can both strengthen and weaken impersonal forces and local structures of inequality. They can thus promote and prevent modern slavery.
Hence, third, these structures capture slavery not as a singular entity, but as a social process that is marked by vulnerabilities, constraints and options that an individual or a group of individuals is facing within certain constellations. For this reason, actors can contribute to modern slavery indirectly and unintentionally.
Ultimately, while definitions of slavery as relation are able to detect incidences of slavery of various kinds, structural definitions uncover constitutive elements and modalities enabling modern slavery.
Modern Slavery: a Pathway
This section discusses modern slavery as relation on the one hand and as structure on the other hand (cf. Table 1). While both terms can be analytically distinguished by means of their definitions, implications and effects, they are not dichotomous, but entangled. They are intermediated and mutually constitutive, because slavery as structure contains relational constellations. This can be understood in a broad way: social structures consist of and are constituted by social relations. Determinants of structure such as poverty or racism are neither natural nor simply given, but products of society. Vice versa, slavery as relation is enabled (or disabled) by the structures within which it is embedded. Structural factors such as social stratification, the supply of work forces (Barrientos et al. 2013) or the density of exploitative employers (Chesney et al. 2019) strongly impact the likelihood and persistence of relations of slavery. Slavery as structure even supervenes upon slavery as relation, as it may affect the latter stronger than the other way around.
Table 1 Two models of modern slavery Modern slavery as structure and modern slavery as relation also share central features. Both acknowledge the involuntary nature of slavery and the exercise of control over the affected person. At the same time, their analytical distinction allows descriptions and explanations that are peculiar to each. Approaches to modern slavery as structure argue that neither the involuntary conduct nor the forms of control exclusively manifest in direct legal, political, physical or psychological coercion. They consider patterns of vulnerabilities, restrictions, and options that enable and promote the enslavement of individuals or certain groups of individuals. Therefore, we do not argue that structures cause slavery, but that structures provide the conditions under which modern slavery manifests.
Modern slavery as relation identifies and describes direct and intentional actions. The identification of a concrete case of modern slavery as relation is an important prerequisite for tackling it. Additionally, by providing and defining distinctive features, approaches to modern slavery as relation are able to distinguish slavery from non-slavery—a distinction that approaches to modern slavery as structure may be struggling with (e.g. O’Connell Davidson 2015).
In conclusion, the relational approach is a starting point to identify cases of modern slavery, while the structural approach allows taking into account less obvious forms of violence, and determining sources, reasons and explanations for modern slavery. The analytical differentiation allows considering modalities of modern slavery and determining which types of modern slavery affect business responsibility.