WASHINGTON (CN) — Judge Ketanji Brown Jackson's path toward becoming the first Black woman and first former federal public defender to serve on the nation's highest court kicked off Monday at the U.S. Senate Judiciary Committee.

Currently a judge on the D.C. Circuit, the 51-year-old Jackson sat for hours as the 22 lawmakers on the committee read opening statements that set the tenor for the week, with Democrats celebrating her resumé and Republicans questioning whether she had a bias against the criminal justice system itself.

The historic significance of Jackson's nomination was not lost on committee Chairman Dick Durbin, who kicked off the first day of the confirmation process with a reflection on the Supreme Court's history.

"The reality is that the court's members in one respect have never really reflected the nation they served," said Durbin, an Illinois Democrat. "When the Supreme Court met for the very first time, February of 1790 in the Exchange Building in New York, there were nearly 700,000 slaves without the right of citizenship in this new nation of nearly 4 million people. Neither African Americans or women had the right to vote. There was no equal justice under the law for a majority of people living in America."

Citing Jackson's background as a Harvard University and Harvard Law School graduate with experience in private practice, public defense, and trial and appeals court adjudication, Durbin called her nomination a remarkable moment in American history while also an unsurprising event given the length of her resumé.

"There are so many young African American women and law students, they're seeing your pursuit as part of their dream. And in other important ways, though, you're no different than many nominees who've come before us," Durbin said. "President Biden nominated you because he knew your qualifications are outstanding."

Jackson was nominated to serve as a trial judge on the U.S. District Court for the District of Columbia in 2012 by then-President Barack Obama. She became a Court of Appeals judge for the D.C. Circuit only last year, taking the seat vacated by now-Attorney General Merrick Garland, himself a former Supreme Court nominee.

If confirmed, Jackson would be the second sitting justice on the Supreme Court with experience as both a trial and appellate judge, the other being Justice Sonia Sotomayor.

From the outset, Republicans questioned Jackson's judicial philosophy, with Senator Chuck Grassley, the ranking Republican on the committee, noting he isn't anti-defense attorney or anti-public defender, but has concerns about the philosophy of some criminal defense attorneys and will need to determine Jackson's approach to law.

"There are Bill of Rights attorneys who want to protect defendants' constitutional rights, then there are what I've called criminal defense lawyers who disagree with our criminal laws that they have policy disagreements with," Grassley said. "And of course, that's a very important difference."

Jackson served as a federal public defender from 2005 to 2007.

Senator Patrick Leahy, a Democrat from Vermont who is the most senior member of the committee, asserted that Jackson's previous job titles were not a liability but an asset to a court that historically lacks professional diversity.

"She is not soft on crime. Her background as a federal public defender would bring an informed perspective of our criminal justice system to the Supreme Court," Leahy said. "I'm proud of being a former prosecutor, but confidence in my prosecution of a case was strongest when I knew the defendant had the best possible representation."

The right to counsel regardless of ability to pay is enshrined in the Sixth Amendment and fundamental to the U.S. justice system.

"To this end, a public defender should be looked at as one of the most honorable roles within our judicial system, and yet we have never had a public defender or anyone served as a public defender on our highest court," said Senator Cory Booker, a Democrat from New York.

Public defenders are rarely nominated to the federal bench, and when they are, they often face accusations of being pro-criminal, arguments Jackson will likely contend with in the coming days.

Grassley promised a "respectful and thorough process" of evaluating Jackson's nomination to the Supreme Court over the course of the next few days.

But Republicans on the committee, including Grassley, made clear their continued resentment about the tone of past confirmation hearings for Justice Brett Kavanaugh and Justice Amy Coney Barrett.

Senator Lindsey Graham, a Republican from South Carolina, told Jackson she would receive a hearing unlike that of Kavanaugh, who was credibly accused of sexual assault and became aggressive during congressional questioning about the allegation during his 2018 confirmation hearings.

Unlike Kavanaugh, Jackson is not accused of any such behavior.

Graham went on to imply Jackson was lucky for not facing the same hostility in her hearings that Kavanaugh did.

"You're the beneficiary of a lot, you're the beneficiary of Republican nominees having their lives turned upside down," Graham told Jackson.

Senator Ted Cruz, a Republican from Texas, echoed Graham's sentiments, accusing Democrats of working to "smear" Kavanaugh.

"I can assure you that your hearing will feature none of that disgraceful behavior. No one is going to inquire into your teenage dating. No one is going to ask you with mock severity 'Do you like beer?'" Cruz said.

Graham voted to confirm Jackson to the D.C. Circuit back in 2021, but the chances of him backing her ascension to the highest court in the land became slim Monday as he questioned why liberal groups such as Demand Justice were backing her nomination, and why the White House selected Jackson over Michelle Childs, Graham's preference for the Supreme Court vacancy.

"Judge Jackson, you say you don't have a judicial philosophy, but someone on the left wants you there," Graham said.

In a statement following in the footsteps of accusations he laid out late last week, Senator Josh Hawley, a Republican from Missouri, alleged that Jackson was lenient when handing down sentences in child-pornography-possession cases during her time as a federal trial judge.

The White House has repeatedly pushed back against this narrative, noting that federal sentencing guidelines for possession of child pornography, not the production of it, have long q been criticized as overly harsh and judges regularly deviate from the requirements.

2021 report from the U.S. Sentencing Commission, which Jackson served on for a time, found that in 2019, only 30% of people convicted of non-production related child pornography offenses were handed down sentences that complied with federal sentencing suggestions.

"I'm not interested in trapping Judge Jackson. I'm not interested in trying to play 'gotcha.' I'm interested in her answers," Hawley said Monday.

GOP lawmakers are expected to dig into Jackson's judicial philosophy during Tuesday's hours-long questioning process, and Senator Marsha Blackburn of Tennessee made clear her intent to grill Jackson about everything from expanding the Supreme Court and critical race theory, accusing Jackson of harboring a "hidden agenda."

"Is it to let violent criminals cop killers and child predators back to the streets? Is it to restrict parental rights and expand government's reach into our schools and our private family decisions? Is it to support the radical left's attempt to pack the Supreme Court?" Blackburn asked rhetorically.

After hours of listening to lawmakers' comments, Jackson spoke for the first time at the conclusion of the hearing, emphasizing her commitment to judicial impartiality.

"If I am confirmed, I commit to you that will work productively to support and defend the Constitution and the grand experiment of American democracy that has endured over these past 246 years," Jackson said. "I have been a judge for nearly a decade now, and I take that responsibility and my duty to be independent very seriously. I decide cases from a neutral posture. I evaluate the facts, and I interpret and apply the law to the facts of the case before me, without fear or favor, consistent with my judicial oath."