Republican Grassley is IG Horowitz's ally. The leaks are being used to tell Mueller he can't immunize specific people because they're going to be targets of referrals.
OIG is most assuredly not corrupt.
IG Horowitz was thwarted repeatedly by 0bama admin, who used Eric Holder's very dubious interpretation of the IG statute to keep OIG from investigating the Justice Department, specifically to cover up Fast and Furious. OIG has had it out for DOJ/FBI ever since.
Grassley, a REAL Republican, pushed for a new IG law that would allow IG to go after FBI, it was finally signed by 0bama when it couldn't hurt him anymore, in December 2016.
OIG has been investigating DOJ/FBI for over a year (a month after the new law was passed.) They're going to bring the hammer down on the corruptocrats at FBI.
When the FBI told Congress "we lost 5 of the most crucial five months of texts," OIG stepped up and said, "we can get those, don't worry."
Doesn’t the State Department also have an Inspector General (or perhaps something similar with a different title), but the position was left unfilled during the entire time that Hillary Clinton was Secretary of State?
“OIG is most assuredly not corrupt. “
They would be the exception then. Even if they are on the up and up, they could only present evidence to the AG for prosecutions, right?
They may have to do a lot more leaking to move the needle with Sessions.