ABSTRACT
Although statistics on crime are among the oldest and most widely available official statistics of modern States, they tend, for several reasons, to be controversial. The first reason is that acts punishable by law are typically committed in secrecy. This implies that most incidents remain hidden from the authorities and that, consequently, officially recorded incidents will always reflect no more than a small part of the true volume. In addition, official statistics on crime are difficult to compare across countries due to variations in legal definitions, reporting patterns and recording practices. In spite of these problems, several treaties have made the collection of international statistics on human trafficking mandatory. The Palermo Protocol obliges parties to collect and share information on trends in organised crime, including human trafficking. 1 Likewise, GRETA, the monitoring body of the Council of Europe Convention on Action against Trafficking in Human Beings, recommends the maintenance of comprehensive statistical systems covering all aspects of human trafficking. 2 Directive 2011/36/EU on Preventing and Combating Trafficking in Human Beings and Protecting its Victims emphasises that “the Union should continue to develop its work on methodologies and data collection methods to produce comparable statistics on trafficking in human beings” (Article 19).
