At the ANU, each PhD student has a panel of (at least) three:
Below, I list all students for which I've been acting as an associate supervisor while primarily acting as a "panel member" without being involved in research.
Every PhD student has several milestones that need to be achieved. One of them is passing the Confirmation of Candidature (CoC) milestone after 9 to 12 months after commencing, where the entire PhD plan (and current progress towards it) gets reviewed. Every PhD panel has an additional CoC chair. This person is in charge of chairing that milestone meeting and acting as yet another, independent observer. He/she will be in charge of making a final recommendation based on everybody's feedback.
I have been or will be a CoC chair for the following students:
At the ANU, the examiner of a PhD thesis is different from the panel and, in fact, has to be conflict-free to any of the panel members. In contrast, in Germany (as well as in many other countries), the main supervisor is always the primary examiner. (Whereas at the ANU examiners are even anonymous unless they voluntarily declare their identity.)
Below, I list all PhD theses that I reviewed/examined in the past: