On the Internet, information is transmitted instantaneously across borders. Enormous volumes of information are collected and stored throughout the world. Information on the Internet can also be subject to criminal investigations. The increasing problem for criminal justice authorities is that the information they seek to access is often stored in other States and is, therefore, outside their jurisdiction. Exercising a state power over data stored inside another State’s territory could be a violation of sovereignty.Discussing cross-border data investigation needs to consider both the sovereignty of the State in which the data are stored and human rights of the investigation subject. These issues are closely related to each other and, thus, likely to be confused. Regarding data collection for investigatory purposes, if there is no infringement of the investigation subject’s human rights, concerns are rarely raised regarding sovereignty infringement. However, the existence of two types of investigation subjects, data subjects and data controllers, complicates the issue.This paper provides an approach to improve cross-border data investigations, with due consideration of human rights and international law, by analyzing current international discussions in this field.