We are witnessing a decade where human activities have led to an unprecedented scale of data collection and processing. Databases are being increasingly used by law enforcement to effectively investigate and prosecute criminal offences. Databases undeniably enhance the efficiency of investigations and assist in the prevention and prosecution of crime. However, the use of databases should also be assessed in relation to the protection of fundamental rights. Given the fact that the storage and processing of data are deployed to control, detect, deter, and prevent crime, databases and privacy are strongly linked. Depending on the case, the important aim of investigating serious crime may not sufficiently justify data retention. With the increasing use of big data, personal data processing takes place in the absence of the concerned individuals whose data is actually being processed. This raises issues related to data regulations and the effectiveness of existing mechanisms of legal protection for data subjects. On a different note, crime is no longer solely a national concern: it crosses jurisdictions and borders with ease. The growing tendency and need for law enforcement to use big data is particularly challenging when the data is stored abroad. Data transfer is particularly problematic if the recipient country cannot ensure an appropriate level of data protection. Because law enforcement authorities’ coercive powers are limited to their national territories, the path to enhanced judicial cooperation in criminal matters and police cooperation is of paramount importance. This is particularly true given the transnational dimension of most of serious crimes. It is essential for countries to cooperate in investigating and prosecuting criminal acts. This is particularly true in Switzerland and Turkey because of their status in the regional context: both lie outside the European Union (EU) but still have a high degree of interaction with the EU. This article deals with concerns relating to privacy protection in the context of data retention and judicial data exchange in Europe. A comparative analysis of Swiss and Turkish legal frameworks with regard to the European Court of Human Right’s case law provides a useful tool in identifying the legal standards that can help strike a fair balance between legitimate interests in database use and personal privacy protection. The specifics of the interplay between the right to privacy and the prevention and combatting crime in Swiss and Turkish cultures also creates a fertile ground to discuss the flaws in existing regulations. To this end, we describe the core principles in database processing with reference to the Council of Europe’s standards. Then we evaluate the legal frameworks of two countries under consideration. Last but not least, we assess the practical implications of these legal frameworks with regard to transmittal of personal data, with reference to the European Police Office.