"Law enforcement officers and prosecutors may never select the timing of investigative steps or criminal charges for the goal of affecting any election, or for the objective of giving an advantage or disadvantage to any candidate or political party", reads a 2016 Justice Department memorandum issued by then-Attorney General Loretta Lynch, which mirrors language issued by previous attorneys general ahead of federal elections.
US President Donald Trump has escalated his attacks on Attorney-General Jeff Sessions, suggesting the Department of Justice put Republicans in mid-term jeopardy with recent indictments of two Republican congressmen.
A graduate of the Wharton School at the University of Pennsylvania (Trump's alma mater), Berman has contributed to numerous Republican candidates including Trump himself.
While there have been exceptions, longstanding protocol holds that the Justice Department should be left to operate free of political influence from the White House.
The president apparently was referring to the current investigations into GOP Reps. Both are creating problems for the GOP, given how hard it would be to replace the already-renominated incumbents on the ballots, and in Trump's estimation, Sessions should have prevented that.
Both congressmen have pleaded not guilty in their cases. "These two men have been charged with crimes because of evidence, not because of who the President was when the investigations began".
Mr Trump's fresh attack on Mr Sessions was the latest development in his long-running feud with the attorney general.
Trump's second tweet is a lie.
Senator Jeff Flake, a Republican, said on Twitter the statement was "not the conduct of a President committed to defending and upholding the constitution, but rather a President looking to use the Department of Justice to settle political scores".
President Trump during a meeting in the Oval Office on August 28.
Mr Trump suggested Mr Sessions could lose his job in July previous year when he said "time will tell" what happens to him. The Hunter investigation began under Obama.
Former Manhattan U.S. Attorney Preet Bharara called Trump's tweet "next level insane, inappropriate, unethical, stupid, incriminating".
Trump also tweeted: "The Democrats, none of whom voted for Jeff Sessions, must love him now". Immediately he became a wonderful man, a saint like figure in fact.