Spencer Overton is president of the Joint Center for Political and Economic Studies and a professor of law at George Washington University Law School.

Every day, more than 13,000 people go to work on Capitol Hill. And they come from across the country — representing every race and ethnicity.

But their bosses — those staffers who represent the top of the food chain — are almost uniformly white.

Even though the current Congress is the most diverse in history, more than 3 out of 4 members of the House are white, and they overwhelmingly surround themselves with staff leaders who look just like themselves — not their constituents.

This is a bipartisan issue: Of the 329 white representatives, just 16 have chiefs of staff who are persons of color: 10 Republicans and six Democrats. Nearly three quarters of all members of the House — 313 members — have no senior staffers of color.

These are among the findings of a comprehensive House staffing analysis conducted by the Joint Center for Political and Economic Studies.

What we learned in doing this study is alarming: An astounding 86 percent of the top decision-makers in the House staff — chiefs of staff, legislative directors and communications directors — are white. Even more alarming, more than a quarter of House members represent districts that are more than 33 percent people of color, yet do not employ a single top staffer of color. These findings build on what we learned in an earlier study about the Senate, where 93 percent of the top 336 staff positions as of 2015 were filled by someone who is white.

While some members may point to diversity in the highest ranks of their district- and state-based offices, the legislation that shapes American lives comes out of Washington. And changing the identity of those working in Washington results in profound changes in policy. Look at what was accomplished after the so-called Year of the Woman in 1992. The election of four new female senators paved the way for the passage of the landmark Violence Against Women Act — a law shaped in part by Senate Judiciary Committee staff director Cynthia Hogan. Women now make up 20 percent of Congress, and they have been central to passage of laws protecting family and medical leave, fair pay, and affordable health care — and even ensuring equal access to restroom facilities in the Senate.

We know that Americans are more likely to elect a person of color to Congress than sitting members are to hire people of color to the top ranks of their staff. Last month, Boston City Council member Ayanna Pressley pulled off a Democratic-primary upset of Michael Capuano, a 10-term U.S. representative. A black woman, Pressley made it clear that she did not disagree with Capuano’s long-standing progressive voting record. She argued that voters in the majority-minority district deserved a representative who more deeply understood their lived experience.

Pressley’s victory builds on other primary upsets by nonwhite candidates — most notably political newcomer Alexandria Ocasio-Cortez’s surprise win over New York Rep. Joe Crowley, the fourth-ranking House Democrat and another 10-term incumbent, also in a district that was overwhelmingly of color.

Assuming they win in November, Ocasio-Cortez and Pressley will join a Democratic caucus that has plainly failed to cultivate leaders from diverse communities. Our research shows that without the Congressional Black Caucus — whose members account for the hiring of 85 percent of all black Democratic top staff — the House would be almost totally devoid of senior staff of color. Less than 8 percent of the top staff in white Democratic members’ offices are people of color, although these offices represent districts that on average include more than one-third residents of color.

Last year, Senate Democrats formally adopted a version of the NFL’s Rooney Rule, which requires that at least one candidate of color be interviewed for each vacant senior position. They also released demographic data on staffing in each office so that the racial disparities between top staffers can begin to close. House Democrats have said they would follow suit, but the entire House of Representatives can and should take this crucial step that would directly transform the top staff makeup in Congress.

Ensuring that top staff in members’ offices more appropriately reflect America is not diversity for diversity’s sake. It’s essential to achieving good, sound public policy. And if white members of Congress continue to fail to recognize and rectify this problem, the public will replace them with representatives who do understand how critical this issue is.

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