A Baltimore native, Judge Jackson writes music, sings, dances and is gifted at mimicry. One of her virtues, she once said, is that she does not take herself too seriously.
Appointed by Mr. Obama in 2011, she took a somewhat unusual path to the federal bench. After graduating from Harvard Law School, she worked for six years as a federal prosecutor in Washington, trying 50 cases. She spent the next eight years in private practice, becoming a partner at the Washington law firm now known as Venable.
Then she took a six-year break from the law to raise her two sons. Returning to practice, she persuaded the defense firm Trout Cacheris to allow her to leave the office every day at 2 p.m. so she could be home for her children.
In sentencing hearings, Judge Jackson sometimes seems to be reading from notes, illuminated by a small blue and white ceramic lamp that adorns her bench. Such preparation, Ms. Gertner said, is the mark of a careful judge determined to guard against bias and the urge to “emote from the bench.”
Friends say she thrives on the kaleidoscope of challenges of a federal courtroom — intellectual, emotional and practical. One friend recalled how once, when one of her high heels snapped off in the middle of a trial, she simply slipped out of her shoes and continued questioning her witness in her stocking feet.
Only the threats against her and her loved ones seemed to have distressed her.
Just last week, Mr. Trump sent ripples of concern throughout the ranks of federal judges by attacking Judge Jackson on Twitter. Judge Beryl A. Howell, the chief justice of the Federal District Court in Washington, declared in a statement that “public criticism or pressure” did not affect the sentencing decisions of “the judges of this court.”
While Judge Jackson has steered clear of political references in court, she has sometimes seemed to counter Trump administration rhetoric. She has insisted that in a courtroom, at least, truth matters, that “facts” are different from “alternative facts,” and that a deliberate effort to “obscure the facts undermines our political discourse.”
Noah Weiland contributed reporting. Kitty Bennett contributed research.