The objective of this paper is to explore the role of human tracking technology, primarily the use of global positioning systems (GPS) in locating individuals for the purposes of mutual legal assistance (MLA), and providing location intelligence for use in inter-state police cooperation within the context of transnational crime. GPS allows for the 24/7 continuous real-time tracking of an individual, and is considered manifold more powerful than the traditional visual surveillance often exercised by the police. As the use of GPS for human tracking grows in the law enforcement sector, federal and state laws in many countries are to a great extent undefined or even contradictory, especially regarding the need to obtain warrants before the deployment of location surveillance equipment. This leaves courts ruling on transnational crimes in the precarious position of having to rely on age-old precedents which are completely void to the new capabilities of today’s tracking technologies. On one side of the debate are civil libertarians who believe the individual’s right to be let alone is being eroded to the compromise of human rights, and on the other side are law enforcement agencies who wish to provide more precise evidence to judges and juries during hearings against suspects (particularly in issues pertaining to national security). This paper argues that there is a radical middle position, the via media: that a warrant process is legislatively defined and not only for MLAs but also to formalise existing informal inter-state police cooperation. Safeguards are required to overcome the potential misuse of human tracking technologies by police officials and others in positions of power. And this particularly in light of the emerging implantable high-tech identification and tracking devices now commercially available.