The president has mused repeatedly about firing Rosenstein, who appointed Special Counsel Robert Mueller previous year after Attorney General Jeff Sessions recused himself. As the Justice Department's #3 official, Ms. Brand admirably led the litigating divisions on the civil side of the department.
Brand, 44, would have been in line to take over the supervision of Special Counsel Robert S. Mueller III's Russian Federation investigation if Deputy Attorney General Rod J. Rosenstein, the Department's No. 2 official, was sacked by Trump or recused himself from the matter, the New York Times reported on Friday.
Rosenstein had approved the extension of surveillance on Carter Page, a former campaign adviser for Donald Trump.
"I am proud of what we have been able to accomplish over my time here", Brand said in a statement.
After release of the memo, a reporter asked the president whether he still had confidence in Rosenstein. She will replace Jeff Gearhart, who retired at the end of January, and will report to President and CEO Doug McMillon.
In a few weeks she will leave to become Walmart's executive vice president of global governance and corporate secretary.
NBC reports that "as far back as last fall, Brand had expressed to friends that she felt overwhelmed and unsupported in her job, especially as many key positions under her jurisdiction had still not been filled with permanent, Senate-confirmed officials". "She is a graduate of Harvard Law School, clerked at the Supreme Court, she worked at the White House, in academia, and has served in leadership positions spanning three administrations".
Deputy U.S. Attorney General Rod Rosenstein and Associate Attorney General Rachel Brand participate in a summit to discuss efforts to combat human trafficking, at the Justice Department, on February 2.
About a third of the 13 divisions in Brand's purview, including the civil rights and civil divisions, remain vacant, according to NBC.
Sources close to Brand said she did not want to be under the political spotlight that the role would likely bring, according to NBC News.