WASHINGTON—Republicans aggressively questioned Supreme Court nominee Ketanji Brown Jackson on Wednesday over her sentences for convicted criminals, while Senate Democrats decried GOP tactics they said were disrespectful and the judge said she would recuse herself from a high-profile college admissions case.

Senate Judiciary Committee Chairman Dick Durbin (D., Ill.) opened the second full day of questioning at Judge Jackson’s confirmation hearing by citing support for Judge Jackson from the Fraternal Order of Police and the International Association of Chiefs of Police.