Breyer, the eldest of the nine judges, was appointed in 1994.
The calls come in the wake of a speech Breyer gave to Harvard Law School students and alumni earlier this week when he warned that court packing could harm the rule of law in the U.S.
Last week a billboard truck that read “Breyer, retire,” drove around Capitol Hill. The printed message also warned, “Don’t risk your legacy.”
Another side of the truck read, “It’s time for Black woman Supreme Court justice. There’s no time to waste.”
The truck was paid for by Demand Justice.
Breyer also said he believes his fellow justices take their oath to be unbiased seriously.
“If the public sees judges as politicians in robes, its confidence in the courts and in the rule of law can only diminish, diminishing the court’s power, including its power to act as a check on other branches,” he said. “My experience of more than 30 years… as a judge has shown me that once men and women take the judicial oath they take that oath to heart. They are loyal to the rule of law, not to the political party that helped to secure their appointment.”
Democrats have been eyeing a number of ways to fight back against the 6-3 conservative majority on the high court, including adding seats to the bench.
Sen. Ed Markey, D-Mass., along with House Judiciary Committee Chairman Jerrold Nadler, D-N.Y., and Judiciary Committee members Jones and Hank Johnson, D-Ga., stood outside the Supreme Court Thursday to announce their new legislation to expand the high court from nine to 13 justices.
House Speaker Nancy Pelosi, D-Calif., said Thursday she doesn’t plan to advance the court-packing legislation to a full House vote.
Biden has implemented a commission to study court reforms, rather than getting on board with the court-packing plan. Pelosi and Sen Dick Durbin, D-Ill., have said they support the commission but are hesitant about packing the court.
Fox News’ Tyler Olson contributed to this report.