Although the investigation into the 2016 presidential election is technically boundless, FBI special counsel Robert Mueller's probe will have to conclude soon or go dark to avoid an appearance of trying to sway elections in the 2018 midterms, The Wall Street Journal reported.

"I think it is the obligation of every reasonable prosecutor to minimize the duration of that cloud or cause lightning to strike as quickly as possible," former federal prosecutor out of New York Preet Bharara, who was fired by President Donald Trump for refusing to resign, told the Journal.

There are some written Justice Department memos aligned to that effect, written by former President Barack Obama's Attorney General Eric Holder, but nothing that would concretely force Mueller to resolve his investigation on the last presidential election or keep him from speaking out on the status of it, as James Comey infamously did twice in 2016.

"There aren't any rules around how we act in the run-up to an election . . . there's a norm, you avoid any action in the run-up to an election that might have an impact, if you can," James Comey told Axios, the Journal reported.

Comey, though, is "sure" Mueller would "operate with that norm in mind" and not do anything to damage Republicans or aid Democrats' hopes to retake control of Congress in the November midterm elections.

A March 2012 memo from former AG Holder leading up to that presidential election instructed his DOJ to be "particularly sensitive to safeguarding the Department's reputation for fairness, neutrality, and nonpartisanship," according to the Journal.

The memo reportedly added DOJ personnel should not time investigations or criminal charges "for the purpose of affecting any election," according to the report.

Mueller and his team are in a precarious position now, and a tenuous time. Any charges of Trump campaign officials will potentially boost Democratic efforts in the midterms. Conversely, any clearing of the Trump administration amid an expensive and ballyhooed probe ignited by the Democrats' losses in 2016 will vindicate Republicans in what President Trump has publicly dismissed as a politically motivated "witch hunt" to provide an excuse for the loss of one of the most expensive campaigns in presidential history.