I don't see where you get this being a political role. What the political parties do with the information once it comes out is up to them. It's up to you what you do with it. The government can use it as well, if they want, to see what has worked and what hasn't, and to take that and to strengthen their programs.
No, I don't think you'd say any of the other commissioners are political, and certainly not the Auditor General, so why would the commissioner's role be a politicized role?