As the 2020 Democratic candidates campaign to secure support from black Americans — a voter segment that will play a crucial rule in choosing the party’s next nominee — reparations for the descendants of enslaved men and women has emerged as something of a litmus test.

The big picture: Many of the candidate have voiced their support for some form of reparations to redress the legacies of slavery and discrimination, but not all are embracing the issue in the traditional sense (direct compensation).

Where they stand

Sen. Cory Booker: Booker introduced a Senate companion version of a House bill by Rep. Sheila Jackson Lee (D-Texas.) that would establish a commission to study the impact of slavery and continuing discrimination against black Americans, and make recommendations on reparation proposals for descendants of slaves. Former Rep. John Conyers (D-Mich.) was first to introduce legislation in 1989;

Sen. Kamala Harris: Harris said in an interview on "The Breakfast Club" in February that she supports government reparations for black Americans. Harris told NPR's "Morning Edition" last month that the term reparations "means different things to different people," and that allocating funds for mental health treatment would be one form of reparations.

Sen. Bernie Sanders: In 2016, Sanders was dismissive of reparations, saying, "First of all, its likelihood of getting through Congress is nil. Second of all, I think it would be very divisive."

During an appearance last month on "The View," Sanders doubled down on his position: "I think that right now, our job is to address the crises facing the American people and our communities, and I think there are better ways to do that than just writing out a check."

However, on April 5, Sanders told Rev. Al Sharpton that, if elected, he would support Democratic Rep. Sheila Jackson Lee's bill, setting up a commission to study reparations. "If the House and Senate pass that bill of course I would sign it ... There needs to be a study," Sanders said the National Action Network conference.

Julián Castro: The former San Antonio mayor and housing secretary under President Obama has arguably been the most vocal candidate on this issue. Castro said he would create a commission to study reparations and determine the best policy proposal.

Castro notably took shot at Sanders by name in an interview last month on CNN, saying: "It’s interesting to me that when it comes to 'Medicare for All,' health care, you know, the response there has been, 'We need to write a big check.' That when it comes to tuition-free or debt-free college, the answer has been that we need to write a big check."

Sen. Amy Klobuchar: In an interview on NBC’s 'Meet the Press' last month, Klobuchar said: "I believe we have to invest in those communities that have been so hurt by racism. It doesn't have to be a direct pay for each person, but what we can do is invest in those communities. Acknowledge what’s happened. ... Making sure we have that shared dream of opportunity for all Americans."

Sen. Elizabeth Warren: She tweeted in support of Jackson Lee's bill last month, saying: "Slavery is a stain on America & we need to address it head on. I believe it’s time to start a national, full-blown conversation about reparations. I support the bill in the House to support a congressional panel of experts so that our nation can do what’s right & begin to heal."

Sen. Kirsten Gillibrand: She said at Al Sharpton's National Action Network's annual convention last week that she supports legislation to study reparations. "This is a conversation that is long overdue," she said.

Beto O'Rourke: Like Sanders, O’Rourke has been less enthusiastic about reparations, but said he supports Jackson Lee's bill.

Marianne Williamson: The best-selling author is the only candidate, despite her long-shot bid, to present a plan with specifics. She proposed $100 billion in reparations or $10 billion a year to be distributed over 10 years for economic and educational projects , Williamson told CNN in January.

Flashback: Neither Barack Obama, the country’s first black president, and Hillary Clinton voiced support for reparations.

"I fear reparations would be used as an excuse for some to say we’ve paid our debt and to avoid the much harder work" of enforcing anti-discrimination laws in employment and housing, lifting people out of poverty, improving public education and rehabilitating young men coming out of prison.

Clinton did not directly answer when asked in 2016 if she supports it.

"I think we should start studying what investments we need to make in communities to help individuals and families and communities move forward. And I am absolutely committed to that. There are some good ideas out there. There’s an idea in the Congressional Black Caucus about really targeting federal dollars to communities that have had either disinvestment or no investment, and have had years of being below the poverty level. That’s the kind of thing I’d like us to focus on and really help lift people up."

Go deeper: Everything you need to know about every 2020 presidential candidate