You wouln’t let a foreign country fiddle with your justice system.
At the moment, any wallet can challenge submissions to the registry. Although it is true that there is the need to include as much people possible to watch over the integrity of the registry, this creates a lack of transparency of the challenging process and creates a gap in which high-PNK holders can collude with bad actors, challenging profiles that have a gray area and influence in the outcome in order to seize the deposit.
I propose that challengers should be people in the registry, or as an alternative, to provide means that prove that they are not related to the jurors in some way (not very realistic or feasible, though).
Transparency is the requirement of any descentralized organization. There is currently no reason for the challenger to remain anonymous, but there are reasons to keep his identity and independence from the jurors as clear as possible. If an anonymous actor can influence the judiciary system of a country from the outside, it would leave it open to foreign powers to leverage their positions for their own benefit.
A recognition to @marcwinn for the seeds of this idea.