Holder made the announcement at a Human Rights Campaign gala in New York City on Feb. 8, 2014. 2014 Taylor Hill

New York – Attorney General Eric Holder on Saturday announced sweeping changes in policy at the Department of Justice that will significantly alter the way same-sex married couples are treated by the nation’s judicial system.

“On Monday, the Justice Department will issue a new policy memorandum that will – for the first time in history – formally instruct all department employees to give lawful same-sex marriages full and equal recognition, to the greatest extent possible under the law,” Holder said in front of a packed ballroom at New York’s famed Waldorf-Astoria hotel at an event for the Human Rights Campaign, a gay-rights lobbying organization.

The policy change will have wide-ranging implications.

Gay couples now have the right to invoke “marital privilege,” meaning they can’t be forced to testify against their spouse in court, even in states that do not currently permit same-sex marriage.

Seventeen states and the District of Columbia now allow same-sex couples to get married. In states that do not allow same-sex marriage, spousal privilege for same-sex couples is not guaranteed.

Same-sex couples can now also jointly file for bankruptcy, and they will be allowed the same visitation rights as their heterosexual counterparts at the nation’s federal prisons.

"Just like during the civil rights movement of the 1960s, the stakes involved in this generation's struggle for LGBT equality couldn't be higher," Holder's statement said. "As Attorney General, I will not let this Department be simply a bystander during this important moment in history.”

The announcement garnered a standing ovation from the crowd of nearly 1000 people, a mixture of corporate sponsors, celebrities and major gay rights activists.

"In every courthouse, in every proceeding, and in every place where a member of the Department of Justice stands on behalf of the United States, they will strive to ensure that same-sex marriages receive the same privileges, protections, and rights as opposite-sex marriages under federal law," Holder said.

The directive will "formally instruct all department employees to give lawful same-sex marriages full and equal recognition, to the greatest extent possible under the law.”

Same-sex marriage supporters hailed the move.

"Today's announcement is one more step to turning the federal government from the number one discriminator against gay people to putting its moral and legal weight on the side of our families and the freedom to marry," said Evan Wolfson, founder and president of Freedom to Marry, an organization committed to same-sex marriage across the nation.

"In addition to continuing to add to the federal programs and protections rightly available to married couples who are gay, including those who live in states that still discriminate, the Attorney General is fulfilling the constitutional imperative of equal treatment under the law," he said.

Sen. Charles Schumer, D-NY, said the announcement showed that Holder's policy change “is bringing our legal system in line with our moral system.”