There is some confusion about the difference between personal data and sensitive personal data and even whether sensitive personal data exists as a term! So, let’s see if we can clarify the situation. Under the old 1998 version of the Data Protection Act (DPA), there was a term ‘sensitive personal data’. Under the GDPR, this is now known as ‘special category personal data’, so we are now concerned with two categories of personal information i.e., personal data and special category data.
Personal data
The GDPR defines ‘personal data’ as any information relating to an identified or identifiable natural person (‘data subject’). At first glance, this is a simpler definition when compared to the definition of personal data in the DPA 1998. However, in effect, the GDPR definition brings a series of identifiers into play including name, online identifiers (such as an IP address) and location data.
Under the GDPR, personal data only includes information relating to natural persons who:
- Can be identified, or who are identifiable, directly from the information in question; or
- Can be indirectly identified from that information in combination with other information.
With the DPA 2018, however, the definition refers to identified or identifiable living individuals and goes on to clarify an ‘identifiable living individual’ as being a living individual who can be identified directly, or indirectly, in particular by reference to:
- An identifier such as a name, an identification number, location data or an online identifier, or
- One or more factors specific to the physical, physiological, genetic, mental, economic, cultural or social identity of the individual.
(Note the word ‘natural’ rather than ‘living’ was used in the GDPR to aid the translation of the term into multiple European languages).
Special Category Data
Special category data, by its very nature, is more sensitive, and so needs more protection. For example, information about an individual’s:
- Racial or ethnic origin, political opinions, religious or philosophical beliefs
- Trade-union membership
- Genetic data, biometric data processed solely to identify a human being
- Health-related data
- Data concerning a person’s sex life or sexual orientation.
Under the GDPR, inclusion of genetic and biometric data is new.
In the UK, special category data previously included information about criminal convictions and alleged criminal offences – this is now treated separately, and its processing is subject to even tighter controls.
But why is it important to recognise the difference? Of course, any category of personal data can be ‘sensitive’ for an individual, but special category data receives additional protection under the legislation. Firstly, all categories of personal data can only be processed lawfully if certain conditions are met and the processing must, in all cases, be necessary. These conditions, commonly known as ‘lawful bases’ are set out in Article 6 of the GDPR and there are 6 to choose from.
If the type of personal data processed falls into the special category data group, its processing is prohibited unless a second condition (set out in Article 9) is also met, or an applicable exemption can be applied. Understanding the definitions is vital, as the processing of special category personal data is also subject to additional conditions, safeguards and exemptions set out in Schedule 1 of the DPA 2018.
So, first and foremost, whether the personal data is sensitive or not, you need to understand what categories of personal data you want to process, how and why. Then, before you begin, you need to determine your lawful basis conditions for processing both categories and ensure you have documented your decisions.
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