South Bend mayor and Democratic presidential hopeful Pete Buttigieg said Thursday that he is no longer using the phrase "all lives matter." Buttigieg referred to the phrase while speaking at Al Sharpton's National Action Network convention, which has become a high-profile event for Democratic candidates.

In his speech, Buttigieg stressed the importance of addressing racial inequalities. "Racial justice must be compatible with being pro-rule of law and respectful of law enforcement doing the right thing. It should enhance, not diminish, the value of a good police department when we assert what should go without saying. But in these times it has to be said clearly, again and again, that black lives matter," Buttigieg said.

Buttigieg had said "all lives matter," a phrase disliked by activists, in his 2015 State of the City address. He also found himself in hot water after he demoted South Bend's first African American police chief, Darryl Boykins, in 2012. Boykins, who was under investigation for corruption at the time, claimed that his demotion was racially motivated.

The Rev. Al Sharpton stands with Democratic presidential hopeful South Bend, Indiana Mayor Pete Buttigieg at the National Action Network's annual convention April 4, 2019, in New York City. Getty

On Thursday, after speaking to the largely African American audience, Buttigieg told reporters he didn't initially realize how the phrase "all lives matter" was used to undercut and "devalue" the Black Lives Matter movement. "Since learning about how that phrase was being used to push back on that activism, I stopped using it," the mayor said.

Get updates from the campaign trail delivered to your inbox

Buttigieg explained that he felt he was faced with a "tough choice" between "holding up the law" and "seeing our community torn apart" when weighing how to handle the Chief Boykins controversy. Regardless, he said the issue made the community stronger, and told reporters that he believes he "would not have been re-elected in minority majority districts unless we had gone through this together and wound up more unified."

Buttigieg also said that some of the things he learned about race and policing were "things we learned the hard way in our community, especially early in my term when I had taken office, serious issues happened around civil rights that led to more mistrust."

Although he isn't officially running for president yet, Buttigieg did say that the "next president needs to set up a Department of Justice that will be ally to help any mayor and police department trying to do the right thing and hold accountable any mayor or police department who is falling short."

The mayor, who is slated to formally announce his 2020 run next weekend, also said he was pushing for an end to mandatory minimums and solitary confinement, which he called "a form of torture," as well abolishing the death penalty.