South Bend, Indiana mayor and presidential hopeful Pete Buttigieg responded to his use of the phrase “all lives matter” in 2015 following a speech on Thursday to Al Sharpton’s nonprofit civil rights organization National Action Network.

As CNBC reported, Buttigieg made the remark “referencing his administration’s refusal to hand over tape recordings of South Bend police officers that remain the subject of legal dispute, as well as the city council’s request that a local police officer stop selling t-shirts that seemed to make light of the 2014 police killing of unarmed black man Eric Garner in New York.”

Said Buttigieg at the time: “There is no contradiction between respecting the risks that police officers take every day in order to protect this community, and recognizing the need to overcome the biases implicit in a justice system that treats people from different backgrounds differently, even when they are accused of the same offenses. We need to take both those things seriously, for the simple and profound reason that all lives matter.”

Buttigieg told reporters that he’s stopped using it and why: “At that time, I was talking about a lot of issues around racial reconciliation in our community. What I did not understand at that time, was that that phrase, just early into mid-2015, was coming to be viewed as a sort of counter-slogan to Black Lives Matter. And so, this statement, that seems very anodyne and something that nobody could be against, actually wound up being used to devalue what the Black Lives Matter movement was telling us, which is what we needed to hear because unfortunately, it was not obvious to everybody that Black lives were being valued the same. So that is the contribution of Black Lives Matter, and it’s a reason why, since learning about how that phrase was being used to push back on that activism, I’ve stopped using it in that context.”