>Following her clerkships, Jackson alternated between jobs with private law firms and public-service positions with the federal government. She worked for the United States Sentencing Commission, an independent agency that studies and establishes sentencing guidelines for the federal judiciary, from 2003 to 2005 and as a federal public defender in Washington, D.C., from 2005 to 2007. In 2010 she returned to the Sentencing Commission as a commissioner and the commission’s vice chair, an appointment (by Democratic Pres. Barack Obama) that required and received confirmation by the U.S. Senate. In that role Jackson and her fellow commissioners made retroactive the 2010 Fair Sentencing Act, which had reduced the disparity in sentences for crimes involving crack cocaine and crimes involving powder cocaine. The commissioners’ action made it possible for defendants who had been convicted under the previous legal regime to seek reduced sentences.
>On September 20, 2012, Obama nominated Jackson to the federal district court of Washington, D.C. After the Senate failed to act on the nomination, Obama renominated her in January 2013, and she was confirmed by a voice vote in March. Jackson was recognized by Supreme Court observers as a rising star and a likely candidate for elevation to a higher court, including possibly the Supreme Court. She reportedly had been on Obama’s short list of candidates to replace Justice Antonin Scalia in 2016—a nomination that went eventually to Merrick Garland, chief judge of the D.C. Circuit, and was then ignored by the Republican-controlled Senate.
https://www.britannica.com/biography/Ketanji-Brown-Jackson