U.S. Government defines human trafficking as:

• 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.
• 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.

Minnesota definition:

Sex trafficking involves recruiting, enticing, harboring, providing, or obtaining an individual by any means to aid in prostitution. It is sexual exploitation and does not require that transportation of, consensus by, or coercion of an adult victim (18 years of age or

Citations:

1: http://www.nij.gov/topics/crime/human-trafficking/pages/welcome.aspx

2: Minnesota Office of Justice Programs. (2014). Human trafficking in Minnesota: A report to the Minnesota Legislature [PDF]. Retrieved from https://dps.mn.gov/divisions/ojp/forms-documents/Documents/2014%20Human%20Trafficking%20Report.pdf