Perhaps a pre-condition to adminhood should be a proven ability to deal fairly with others.
But that wasn't the problem. I don't blame the admin with not dealing fairly with others. I can't even say for sure whether the admin broke any policies.
The problem isn't the admin. The problem is that admins are given discretion over such things in the first place. Speedy deletions should be reserved for indisputably bad articles - articles that no one would seriously oppose the deletion of.
Of course, deletion was supposed to be reserved for such articles as well, but it's devolved into a popularity contest which defines 2/3 as consensus. Fortunately, it's usually possible to export an article before it's deleted via VfD. Unfortunately, it's rarely possible to export a speedy deletion before it's been deemed unworthy. It has been proposed on the pump (one of them) that deleted articles be available for editors to view, but as one of our members of the Board of Directors opposes it it's unlikely to happen.
Anthony