It is not black/white. If you have a qualified candidate that asks less money and reject them over a less-qualified candidate on the sole grounds they worked for a prediction marked, it could be called silly. If the discprancy in qualification and salary demends is high enough and you do this repeatedly, it can be gross misconduct and not only a reason to be fired, but to be held financially liable for the damage.

> If the discprancy in qualification and salary demends is high enough and you do this repeatedly, it can be gross misconduct and not only a reason to be fired, but to be held financially liable for the damage

Again, major caveat, if you do it without disclosing your reasons, possibly. And unless you're personally profiting from it in some way, highly doubtful on financial liability. (Disclaier: not a lawyer.)