One autumn morning in 2003, Federal Park Police stormed into an apartment four miles east of the United States Capitol. Police discovered a semi-automatic handgun tucked between some sheets in a laundry basket after using a battering ram and ordering everyone to get on the ground.

Despite a dispute over who owned the 9 mm pistol, police arrested Andrew Littlejohn and a jury found him guilty of a gun charge. When Littlejohn filed an appeal, he was assigned a public defender, Judge Ketanji Brown Jackson, a little-known Harvard-trained lawyer who is now poised to become an associate justice on the Supreme Court. Jackson, who specialized in appeals at the time, won the case. The charge was dropped by the Park Police, and Littlejohn, who has since relocated to Texas, has kept a close eye on his former lawyer’s career ever since.

When asked about President Joe Biden’s decision to nominate Jackson to the Supreme Court, Littlejohn said, “It’s about time.” “She never tried to brush me off or avoid answering my calls. That’s what struck me the most about her: she made time when she didn’t have to.”

Jackson, who is now a federal judge on the same appeals court that heard Littlejohn’s case, is being hailed by supporters as the first former federal public defender to be nominated to the Supreme Court. Supporters argue that her two-and-a-half years on the bench will bring a much-needed fresh perspective to a court where two current justices, Samuel Alito and Sonia Sotomayor, previously served as prosecutors.

However, Jackson’s defense work and some of her former clients are almost certain to cause a commotion at her confirmation hearings, which begin on March 21. Jackson has faced many of the same questions in previous confirmation hearings, often from the same Republican members of the Senate Judiciary Committee.

However, experts believe that the criticism leveled at public defenders may explain why there are so few judges today. According to a review of Federal Judicial Center data, only about 6% of federal judges list “public defender” on their biographies. According to a study conducted last year by the libertarian Cato Institute, 318 federal judges have a background in prosecution, compared to 58 who have worked as public defenders.

In a background document sent to journalists minutes after Biden nominated Jackson for the Supreme Court, the Republican National Committee accused her of “defending terrorists.” The criticism echoed a line of questioning from Arkansas Senator Tom Cotton during Jackson’s confirmation hearing for the D.C. Circuit last year.

The case, like many others, became bogged down in the federal court system due to motion filings and arguments. Jackson resigned in late 2008 after leaving the public defender’s office to work in private practice. Gul was returned to Afghanistan by the Obama administration six years later, in 2014. Republicans aren’t the only ones who have peppered judicial nominees with questions about their clients. Democrats questioned several of President Donald Trump’s nominees, including Judge Kyle Duncan, who was narrowly confirmed by the Senate in 2018 for a seat on the U.S. Court of Appeals for the Fifth Circuit in Louisiana.

In addition to Littlejohn and Gul, Jackson successfully defended a former attorney who was convicted of tax evasion after accepting a Mercedes Benz from a drug dealer and client as payment. She also successfully represented a man who pleaded guilty in 2002 to possessing equipment to make false identification in order to defraud banks.

Because Jackson handled appeals, her cases often turned on technical issues regarding how trials were conducted. The judge in the Littlejohn case used a compound question to determine how prospective jurors felt about law enforcement. Jurors were instructed to raise their hands only if they had a personal relationship with a police officer – say, a spouse or sibling – and believed that connection would impair their impartiality.

Last year, Jackson told senators that her work as a public defender had given her insight into the judicial system – not in terms of changing her opinion on how cases should be decided, but rather in how they are explained. She was struck at the time by how little criminal defendants knew about the legal system.