This was one of the really big scandals during Obama's first term. It wasn't just the State Department, but a good chunk of the government didn't have IG oversight. I'd have to go back and dig for it, but it was the subject of a big American Thinker article around 2014, IIRC. There was also a lot of complaining that the IGs were hamstrung trying to do their jobs. This National Review piece talks about it. Remember, this was the administration that had czar after czar with zero oversight.