Lawfulness
Reviewing legal basis, purpose limitation and data minimisation together
A legal basis does not legitimise an arbitrary scope of data. Purpose, necessity and transparency must be documented as one connected decision.
8 minute read · Content as of 21.07.2026
The purpose comes before the data collection
A concrete purpose makes it possible to check which data is really needed, who may use it and when it is no longer necessary. Vague just-in-case purposes prevent this delimitation.
Every legal basis has its own conditions
Contract, legal obligation, legitimate interest and consent are not interchangeable labels. Document the preconditions, balancing tests, options to withdraw or object, and the matching information for data subjects.
- Phrase the purpose in everyday language
- Check data fields against necessity
- Record the legal basis and the supporting evidence
- Treat changes of purpose as a new decision
Sources used
- General Data Protection Regulation (EU) 2016/679 · EU · check the consolidated version
- Guidelines for Controllers and Processors · EDPB
- Privacy management, RoPA, DPIA and incident templates · KaitoSec