Trump could replace her with someone who won’t mind firing Mueller.

From Vox; By 

Rachel Brand, the No. 3 official at the Department of Justice, is resigning after just nine months on the job — a decision with big ramifications for special counsel Robert Mueller’s investigations.

Here’s why: Deputy Attorney General Rod Rosenstein is currently in charge of overseeing the Mueller probe. Rosenstein has said that he won’t fire Mueller without good cause.

But if Trump were to fire Rosenstein, or if he were to recuse himself from the investigation or quit outright, the responsibility for overseeing the probe would go to the next in line: Associate Attorney General Rachel Brand.

Which means that whoever Trump picks to replace Brand could potentially end up in charge of the Mueller investigation. Technically, the next in line is Solicitor General Noel Francisco, who is now serving in Brand’s role in an acting capacity. But legal experts told me that Trump has the authority to name anyone he wants to replace Brand.

And here’s the scary thing: That person might follow Trump’s order to dismiss the special counsel.

That can only happen if Rosenstein no longer oversees Mueller — and that’s still a distinct possibility for three reasons.

First, Rosenstein could recuse himself from overseeing Mueller because he had a hand in firing former FBI Director James Comey. Mueller became the special counsel becauseTrump may have let go Comey go in order to obstruct the Russia investigation. So if Rosenstein recuses himself — legal experts, like Jack Goldsmith at Lawfare think he should — then Mueller’s boss becomes whomever Trump may soon name.

Second, Trump could simply fire Rosenstein — and there’s reason to think he might. Trump allies expected last week’s release of the memo from Rep. Devin Nunes would prompt Rosenstein’s dismissal. Trump has consistently made his displeasure with Rosensteinknown, at one point claiming he’s “a Democrat” even though Rosenstein is a lifelong Republican.