If Rosenstein recuses himself from oversight of the special counsel investigation, that role would fall to the Justice Department's No. 3 official, newly confirmed Associate Attorney General Rachel Brand.
Trump's digital volley appeared to be trained at Deputy Attorney General Rod Rosenstein, who recommended the firing last month of James Comey - an nearly unprecedented move that could yet imperil Trump's presidency. Rosenstein authored a compelling memo recommending Comey's dismissal, but seemed to lose his nerve after Trump offered conflicting reasons and said he was going to fire Comey no matter what Rosenstein said.
Until Trump's Friday-morning Twitter burst, only the Washington Post's sources had indicated that Trump was being investigated for possible obstruction of justice.
Questions have been raised about the future of Mueller's role, especially given his appointment of several attorneys who have either represented the Clinton Foundation in the past or were themselves donors to the Hillary Clinton campaign for president to serve beneath him in the investigation.
ABC News reported Friday that Rosenstein has privately acknowledged he may need to recuse himself from the Russian Federation investigation but has yet to seek a formal opinion on the matter.
Democratic Senator Dianne Feinstein, a Senate Intelligence Committee member, said she was "increasingly concerned" Trump would try to fire not only Mueller, but also Rosenstein.
Adding to the confusion is the fact that the special investigation is being led by another former FBI director.
However, since the table is turned now, Trump is feeling like "he is the victim of a conspiracy aimed at discrediting his presidency and ultimately ending his tenure of the White House". The official demanded anonymity because the official was not authorized to be named discussing the deliberations.
The order from the general counsel for the transition team casts a wide net on documents that could shed light on ties between Trump's presidential campaign and representatives of Russia's government.
If that happens Mike Pence will soon become the 46th President.
But then Rosenstein made the surprise move to appoint Robert Mueller as special counsel to lead the Russian Federation investigation, a development that people close to Sessions and Trump believe has worsened matters for everyone involved.
Others have pointed to news that Mueller interviewed with Trump for the Federal Bureau of Investigation director post after Comey's firing. You don't have to be a Trump partisan to have concerns about where all of this headed. "Witch Hunt", the president wrote in a Friday tweet. "Witch Hunt", the president wrote on Twitter. In the same interview the President suggested that he was thinking about the Russian Federation investigation at the time he terminated Comey.