At a previous employer I had people that we just hire be our +1 and shadow the interview process, if they wanted to of course. They really appreciated this sin

At a previous employer I had people that we just hire be our +1 and shadow the interview process, if they wanted to of course. They really appreciated this since it showed them that there was no hidden conspiracy in the process, we were giving everbody that applied the same opportunities to be accepted, and we showed then that throughout the process we were actually trying to find a fit for a person within the company instead of trying to find reasons to reject them. This also gave the new candidate the chance to aks the new hire questions related to their own interview process and first impressions in the company and eased the tension a bit. If they wanted to carry on and participate in interviewing the next session we would let them lead the challenge, with me shadowing, to gain confidence and experience, and later on, if they still wanted to carry on, they would be fully qualified to do interviews just like other members of their team (unless of course they really weren't capable, but that never happened). So I would say the approach really matters when discussing things like this. For us it was a positive.