I'm not here to speak to the appointments process, and it wouldn't be within my purview to do that. I would just highlight, though, that the board of referees is a layperson panel, whereas the umpires are an arm's-length judicial tribunal of people who are former judges from the various levels of courts. So there are indeed differences between the competencies and background requirements for umpires and for referees.
On March 22nd, 2011. See this statement in context.