Starting in 1990, the Inter-American Commission began creating thematic rapporteurships in order to devote attention to certain groups, communities, and peoples that are particularly at risk of human rights violations due to their state of vulnerability and the discrimination they have faced historically. The aim of creating a thematic rapporteurship is to strengthen, promote, and systematize the Inter-American Commission's own work on the issue. The IACHR had the same goal in mind when it created the Unit for Human Rights Defenders in 2001, which in 2011 was transformed into a Rapporteurship.

In the IACHR Rules of Procedure approved during the 132nd regular session—held July 17-25, 2008—the Inter-American Commission reformed Article 15 on "Rapporteurships and Working Groups," and introduced for the first time in that instrument the concept of the "thematic rapporteurship."

The current Rules of Procedure, approved in the 137th regular session—held October 28 to November 13, 2009—establishes that offices of rapporteurs "may function as thematic rapporteurships, assigned to a member of the Commission, or as special rapporteurships, assigned to other persons designated by the Commission."

Generally, thematic rapporteurs are designated by the IACHR during its first session of the year, but under the Rules of Procedure, these appointments may be made "whenever necessary." The Rules of Procedure also establishes the parameters the Commission uses to designate special rapporteurs and establishes that they serve for a three-year term, which may be renewed once.