The first Facebook question posed to the Democratic presidential candidates during the debate on Tuesday in Las Vegas was straightforward: Do they believe all lives matter, or that black lives matter?
Though several Democratic candidates have stumbled while talking about race relations during their campaigns, they seemed well-coached this time around.
"Black lives matter," Vermont Sen. Bernie Sanders said. "We need to combat institutional racism from top to bottom."
Black lives matter activists have interrupted Sanders rallies several times during his campaign, and he has since broadened his frequent speeches on economic inequality to include talk of racial inequality.
Former Maryland Gov. Martin O'Malley was at one of those rallies as well, and he responded to the interruption by saying "all lives matter." He quickly apologized, and on Tuesday tried to explain what he thinks "black lives matter" means.
"The point that the black lives matter movement is making...is that we have undervalued the lives of black people and people of color," O'Malley said. "Black lives matter and we have a lot of work to do to reform our criminal justice system and reform race relations in this country."
Former Secretary of State Hillary Clinton used the question to talk about her plans to reform the nation's criminal justice system, plans she has yet to divulge in detail.
"We need to tackle mass incarceration," Clinton said. "We cannot imprisoning more people than anyone else in the world."