Publicly available data can be systematically analyzed, particularly for the investigation of crimes related to Bitcoin and other cryptocurrencies. This is possible because the transaction data of Bitcoin is publicly accessible due to the functioning of blockchain technology. Regarding the permissibility of such analyses, one aspect examines whether and at what threshold a justifiable infringement of fundamental rights occurs. On the other hand, it investigates whether there is sufficient constitutional justification for an infringement of fundamental rights within the criminal procedure code. The key factor is whether such an infringement of fundamental rights is still considered minor in the sense of §§ 161, 163 of the Criminal Procedure Code.