I assumned he was thinking of something above board and legitimate, not sub rosa. For the same reasons that the rest of us get investigated before we can get certain jobs.
Of course we can't have the CIA or FBI "vetting" cannidates for elective office. But it would be nice if the "press" would do that, since it is supposed to be their job. They investiaged the snot out of Sarah Palin, but when it came to BHO, or any other socialist/liberal, they cover their eyes, plug their ears and warble as loudly as they can. Or they go into this routine: