Democratic presidential candidate and former congressman Beto O'Rourke speaks during a campaign stop in Manchester, N.H., on Saturday. (Brian Snyder/Reuters)

Speaking to black voters and leaders in April, former Texas congressman Beto O’Rourke announced that he supports legislation to study reparations for African Americans as a corrective to “the injustices that have been visited and continue to be visited on people.”

At the time, though, the Democratic candidate didn’t know how directly his own family had contributed to those historical injustices. On Sunday, O’Rourke revealed that both he and his wife, Amy Sanders O’Rourke, recently learned that their ancestors owned slaves.

“Something that we’ve been thinking about and talking about in town hall meetings and out on the campaign — the legacy of slavery in the United States — now has a much more personal connection,” O’Rourke wrote on Medium.

O’Rourke’s revelation, which was sparked by the Guardian’s investigation into his roots, comes as reparations have emerged as a litmus test for Democrats seeking the White House. Last week, reports that ancestors of Senate Majority Leader Mitch McConnell (R-Ky.) owned slaves raised questions about whether those historical crimes are relevant for politicians weighing the issue today.

McConnell, who opposes reparations, has denied that his family’s legacy should impact his stance, noting that tracing the history of slaveholding is complex enough that even former president Barack Obama had forebears who owned slaves.

But to O’Rourke, learning of his own familial ties to human bondage crystallized the benefits slave trading bestowed on his clan — and the need to correct those lasting effects today.

“I benefit from a system that my ancestors built to favor themselves at the expense of others,” he wrote. “That only increases the urgency I feel to help change this country so that it works for those who have been locked-out of — or locked-up in — this system.”

His post came after the Guardian used the genealogy website Ancestry.com to investigate his family’s history, noting that on the campaign trail, O’Rourke had called on all white Americans to account for slavery by “telling, learning and sharing” their history.

The newspaper found that Andrew Cowan Jasper, a great-grandfather of the Texas politician’s grandmother, owned two women in the early 19th century in Kentucky. The slaves, named Rose and Eliza, were priced at $800 each in an estate sale after Jasper’s death.

The Guardian’s research also turned up evidence that O’Rourke’s great-great-grandfather, Columbus Marion Williams, joined the Confederate forces at age 16 along with his father, Frederick Samuel Williams, then 44. O’Rourke noted on Medium that Frederick Williams “most likely” owned slaves as well.

O’Rourke’s wife, Amy, also had a slaveholding relative, the Guardian found: Richard B. Levy, a Virginia planter who fought with the Confederates and was even at Appomattox in 1865 when Robert E. Lee surrendered.

Those long-ago connections to slavery still matter today, O’Rourke argued on Medium, because they help explain lingering gaps in wealth and power between white and black Americans.

“Ownership of other human beings conferred advantages not just to Andrew Jasper and Frederick Williams, but to Jasper’s and Williams’ descendants as well,” he wrote. “They were able to build wealth on the backs and off the sweat of others, wealth that they would then be able to pass down to their children and their children’s children. In some way, and in some form, that advantage would pass through to me and my children.”

Conversely, Rose and Eliza — the slaves owned by Jasper — didn’t profit from their labor, and neither would have their children.

“That those enslaved Americans owned by my ancestors were denied their freedom, denied the ability to amass wealth, denied full civil rights in America after slavery also had long term repercussions for them and their descendants,” he wrote. “The way that fortune was passed through the generations from Andrew to me, misfortune was passed through the generations from Rose and Eliza to their descendants who are alive today.”

O’Rourke’s revelations come as his campaign has struggled to rise above a crowded field of presidential hopefuls, with dwindling enthusiasm and polls regularly trailing the five leading contenders.

Although Obama opposed reparations as impractical, as did Hillary Clinton and Sen. Bernie Sanders (I-Vt.) in 2016, the idea has gained support among 2020 contenders, with many — including O’Rourke — backing a bill from Rep. Sheila Jackson Lee (D-Tex.) to create a commission to study the idea. A House hearing on the plan drew impassioned testimony last month from actor Danny Glover, writer Ta-Nehisi Coates and others.

Reparations have been roundly dismissed by Republicans. McConnell argued that “it’d be pretty hard to figure out who to compensate” and that America had dealt “with our original sin of slavery by fighting a civil war, by passing landmark civil rights legislation. We’ve elected an African American president.”

On Sunday evening, Sen. Ted Cruz (R-Tex.) lashed out at O’Rourke’s reasoning for backing reparations, contrasting the new research with his own family’s immigrant roots.

While O’Rourke has backed Jackson Lee’s bill to study and propose reparations, he’s previously stopped short of supporting financial compensation for African Americans. In June, he told the Root that cash reparations would never find political capital without more education first.

“I think part of the problem is that not everyone knows that story,” he said. “In a democracy, unless you have the political will to take a very tough step, you’re not going to be able to do it.”

It’s not clear whether O’Rourke’s newly discovered family history has changed his thinking. In his Medium post, he pledged to bridge racial gaps by directing billions toward minority schools and businesses and wrote that he “will continue to support reparations, beginning with an important national conversation on slavery and racial injustice.”

O’Rourke also urged others to probe their family histories to learn their personal ties to slavery.

“We all need to know our own story as it relates to the national story, much as I am learning mine,” he wrote. “It is only then, I believe, that we can take the necessary steps to repair the damage done and stop visiting this injustice on the generations that follow ours.”

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