The authors of this article are engaged in anthropological research on the links between the growing interest in privacy and data security as a technical field and how notions of trust, security and accountability are practised in and beyond technical fields of cryptography, specifically a field called multi‐party computation (MPC). They pursue the relationship between trust in different forms of cryptography – academic and activist – and notions of trust as they are articulated in relation to data security and the protection of citizens’ data. There is a tension between the concerns raised in public debates about data security and the promises of emerging cryptographic protocols. In political speeches and public debates, citizens’ trust that governments and tech companies will protect their data is framed as important and essential. In the environments of emerging cryptographic technologies, such as blockchains, bitcoin and MPC, a promise to provide ‘trustless trust’ and abandon the need for trusted intermediaries, authorities and institutions is articulated.