Harris announced her opposition to Sessions at a California labor breakfast honoring Martin Luther King Jr. and other social-justice leaders.
She later took to Twitter to denounce Sessions, who was once deemed too racist to be a federal judge, and said she would vote against his nomination to join Trump’s administration.
“I have deep concerns about Jeff Sessions ability to defend the rights of all Americans ― I will be voting against this confirmation,” Harris wrote. She continued:
Harris joins other Democrats in rejecting Sessions, including Sens. Al Franken (D-Minn.), Cory Booker (D-N.J.), and Senate Minority Leader Chuck Schumer (D-N.Y.).
Harris, in her first weeks on the job, is already making a name for herself in the Senate. She has started an online petition calling on other senators to oppose Sessions.
Harris spent six years as California’s attorney general before being elected to the Senate ― the second black woman ever elected to the upper chamber. She has vigorously denounced Trump.
Sessions, meanwhile, has been accused of calling a black attorney “boy,” calling civil rights groups “un-American” and even saying that his only issue with the Ku Klux Klan is drug use.
Despite Democrats’ opposition, Sessions will likely win confirmation in the Republican-controlled Senate.
This article has been updated to note Harris’ appearance at a California labor breakfast.