Human Trafficking Into and Within the United States: A Review of the Literature. Introduction


This paper presents a comprehensive review of current literature on human trafficking into and within the United States.  This review of the literature is part of a larger study funded by the U.S. Department of Health and Human Services (HHS), Office of the Assistant Secretary for Planning and Evaluation, to examine how HHS programs are currently addressing the needs of victims of human trafficking, including domestic victims, with a priority focus on domestic youth.  This study is also structured to identify barriers and promising practices for addressing the needs of victims of human trafficking, with a goal of informing current and future program design and improving services to this extremely vulnerable population.

While historically there have been inconsistencies and disagreements regarding the definition of human trafficking among politicians, practitioners, and scholars (Laczko & Gramegna, 2003; Richard, 1999), for the purpose of this literature review, the legal definition of human trafficking set forth in the Trafficking Victims Protection Act of 2000 (TVPA) will be used. In the TVPA, Congress defines severe forms of trafficking in persons as:

  1. Sex trafficking in which a commercial sex act is induced by force, fraud, or coercion, or in which the person induced to perform such act has not attained 18 years of age; or
  2. The recruitment, harboring, transportation, provision or obtaining of a person for labor or services, through the use of force, fraud, or coercion for the purpose of subjection to involuntary servitude, peonage, debt bondage, or slavery (8 U.S.C. § 1101).

To conduct a comprehensive review of the literature associated with the trafficking of foreign nationals into the United States and of U.S. citizens and legal permanent residents within the country,[1] we performed multiple searches of the literature using Google and EBSCOhost® search engines. In particular, within the EBSCOhost search engine, we searched the following databases: Academic Search Elite, PsycINFO, PsycARTICLES, ERIC, and PsycEXTRA.[2] Our initial searches featured a wide array of directly related terms, including: trafficking in persons, human trafficking, trafficking/youth/adult, international trafficking, domestic trafficking, sex trafficking, sexual exploitation, child prostitution, commercial sexual exploitation of children, forced labor, labor trafficking, labor exploitation, minor (persons younger than age 18) trafficking victims, debt bondage, domestic servitude, involuntary servitude, and modern day slavery. Most of the research, particularly research published in peer-reviewed journals, was limited to qualitative and quantitative studies of the scope of the problem (i.e., who is vulnerable to trafficking and the characteristics of those who are trafficked).  Information on the needs of trafficking victims and the services provided to this population was limited to information contained in Federal reports, non-peer reviewed journals, manuals and fact sheets, Web sites for advocacy organizations and nongovernmental organizations (NGOs) working with trafficking victims, recently published books on trafficking, and personal communications with direct service providers and trafficking survivors.  Given the state of the field, with the limited research that is available on this issue, personal communication was relied on for many portions of this review to supplement the available literature.  Only first names are used in the citations, to protect the identity of the survivors interviewed for this study.

To collect more rigorous information on promising or effective practices or strategies for serving victims of human trafficking, we expanded our search to related disciplines and victim populations, including: prostitution,[3] torture victims, refugees, asylum seekers, homeless/runaway/throwaway youth, juvenile justice system, adolescent substance abuse, child and adolescent mental health, trauma, co-occurring disorders, domestic violence and sexual assault, and child protective services.  The search criteria were refined further by specifically seeking literature related exclusively to adults (women and men) and minors (girls and boys).  This search revealed significantly more research-focused articles evaluating substance abuse, domestic violence, mental health, and trauma-related services for adults and youth in general.  While not specific to human trafficking, information obtained from these latter searches provides important context about key service delivery systems needed by victims of human trafficking.  It should be noted, however, that even with a broader search, very little information was available regarding the specific needs of and service response for victims of labor trafficking.  This is a significant gap in the literature that is only recently being addressed through calls for research by Federal agencies focused on labor trafficking and, in particular, male victims of labor trafficking.

The results of this comprehensive review are organized by the following key questions:

  • What is human trafficking?
  • How prevalent is human trafficking into and within the United States?
  • Who are the victims of human trafficking?
  • What are the needs of victims of human trafficking?
  • How are victims identified?
  • What services are victims of human trafficking eligible to receive?
  • What are the barriers to and challenges in accessing and providing services?
  • What are promising practices for serving victims of human trafficking?

This review of the literature provides one of the first comprehensive syntheses of information available on human trafficking into and within the United States.

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