Attorney General Eric H. Holder Jr. on Tuesday called on states to repeal laws that prohibit felons from voting after their release from prison, urging changes that could allow millions more across the country to cast ballots.

In a speech at Georgetown University Law Center, Holder said, “It is time to fundamentally reconsider laws that permanently disenfranchise people who are no longer under federal or state supervision.”

Holder said that current laws forbidding felons from voting make it harder for them to reintegrate into society. He pointed to a recent study that showed that felons in Florida who were granted the right to vote again had a lower recidivism rate.

“These restrictions are not only unnecessary and unjust, they are also counterproductive,” Holder said. “By perpetuating the stigma and isolation imposed on formerly incarcerated individuals, these laws increase the likelihood they will commit future crimes.”

Holder does not have the authority to force states to change their laws, but his request could influence the debate to restore voting rights. His appeal is part of a broader effort underway by the Justice Department to overhaul the criminal justice system, which U.S. officials say often treats minority groups unfairly.

The attorney general said that after the Civil War, laws that prohibit felons from voting were a way for post-Reconstruction states to keep blacks from casting ballots. Today, an estimated 5.8 million Americans are not allowed to vote because of current or previous felony convictions. Of those, nearly 38 percent are black.

The Justice Department said that 23 states since 1997 have enacted voting rights overhauls. They include Nebraska, Nevada, Texas and Washington state.

In Virginia, former governor Robert F. McDonnell (R) enacted a policy last year that allowed those with non-violent felony convictions to have their voting rights automatically restored. But critics say the effort still leaves many disenfranchised.

Virginia is one of four states where voting rights are not restored automatically when felons are released from prison.

The Justice Department said that 11 states, including Florida and Kentucky, restrict voting rights for felons. Holder said that 10 percent of Florida’s population is disenfranchised.

Voting rights activists are trying to change the law in that state to make it easier for “returning citizens” to vote. The push could become a campaign issue in Florida’s gubernatorial election this year.

In Kentucky, a bill to restore felon voting rights to those not convicted of certain lascivious or violent crimes gained momentum last month in the state legislature.

“These laws deserve to be not only reconsidered, but repealed,” Holder said.

According to a 2002 academic study on voter disenfranchisement, former vice president Al Gore might have prevailed in the 2000 presidential election had felons been allowed to vote nationwide.