I imagine that high profile individuals and celebrities would have restricted access flags added to their electronic records, much like patients who are under safeguarding arrangements or looked after children. These restrictions are fairly easy to override if you have a legitimate reason, but the system requires you to select a justification (such as clinical necessity or administrative update) and usually enter a comment explaining why you accessed the record—for example, “Printing referral at doctor’s request” or “Overriding to inform patient of appointment.” If the access is later audited, there is at least a documented reason and explanation (which is why I always write War and Peace when I override the system - to protect myself).
In practice, someone with dishonest intentions could potentially exploit legitimate workflows. For example, they might claim a doctor was having problems with their login and asked them to check something on their behalf, or say they needed to read the previous clinic letter to determine the patient’s outcome (which happens a lot at my work place). Another plausible excuse could be that the patient had phoned asking for an update about their appointment. Rather than searching by name, they could search using the patient’s NHS number or date of birth (as though they have phoned up and asked them their date of birth/NHS number), making the access appear routine at the patient’s request.
I remember someone who purposely “lost” patient’s paper outcome (several times) so that, when they were later asked by a supervisor to chase up the outstanding outcome, they had an excuse to access the patient’s last letter. When another colleague reported her, she defended herself with, “The patient was on the late outcome list and I was asked to investigate.” Because that was a legitimate work related justification, nothing ever came of it.
Ultimately, electronic access controls create an audit trail and can deter inappropriate access, but they cannot completely prevent someone from abusing legitimate reasons for viewing records. Similarly, if someone has authorised access to physical paper notes, it is difficult to stop them from looking through them for reasons unrelated to their work.