The 113th Congress is the most diverse in history, with a record number of women elected (101 across both chambers) and a variety of other firsts, including the first openly gay senator, Hindu representative, and Buddhist senator. And after the election of the first African-American president in 2008, there is a real possibility that one of the major party candidates in 2016 could be a woman. Still, U.S. political institutions are not nearly as diverse as the population at large. Out of 535 members of the U.S. Congress, only 20% are women, despite making up half the population; African-Americans make up less than 10% of Congress and Latinos only 8.3%, despite making up 13% and 17% of the U.S. population, respectively.

Research suggests a number of reasons why women and minorities remain under-represented in U.S. politics. A 2010 study by Loyola Marymount and American University found that women were 29% less likely than men with similar credentials to assess themselves as “very qualified” to run for office. Women also have concerns that they may face gender bias in the political arena. Candidates from racial and ethnic minorities face other challenges: During campaigns, minority voters are less likely to be contacted by major parties, and evidence also suggests that prejudice may harm minority candidates’ chances. According to a 2011 study from U.C. Davis, Barack Obama may have won as many as 14 additional states in the 2008 presidential election count if all states had relatively low levels of prejudice.

But how important is it to have politicians who reflect the people they serve — and why? The election of minority politicians may be of symbolic and social importance — for example Obama’s election was linked to a decreased perception of racial discrimination in the United States, particularly among Republicans and conservatives. There is also evidence that female legislators can be more effective, “bringing home” around 9% more federal spending than when the same district is represented by a man.

A 2014 paper published in the Annual Review of Political Science, “When and Why Minority Legislators Matter,” assesses whether electing candidates from racial or ethnic minorities better represents the interests of constituents that make up those minorities. The author, John D. Griffin of the University of Colorado, explores how the presence of minority legislators can affect the political participation of minorities, how such candidates affect voter decision-making and how their prevalence impacts the composition of political parties and the dynamics of policy making.

The study’s findings include:

• Measured through roll-call votes, committee membership or bill sponsorship, black and Latino legislators often better represent their respective groups’ concerns than non-minority legislators. This is true even where the views of minority constituents change according to their electoral district — for example, urban versus rural districts, or those that are more or less affluent.
• Increasing the proportion of minority legislators through redistricting and creating minority-majority districts could be counterproductive. Minorities may gain one more legislator but this can be at the expense of several more legislators even less concerned with the issues most important to minorities.
• The evidence is mixed as to whether the presence of minority candidates boosts the participation of minority voters. An earlier study focusing on black mayors found that they increased participation and political engagement, but “it may be that the executive (rather than the legislative) office and the closer proximity of most mayors combine to have a more pronounced effect.”
• It is not clear whether white voters are less likely to support minority candidates. A study of the 1989 New York mayoral race showed a significant discrepancy between pre-election polls and Election Day returns for David Dinkins and Rudolph Giuliani. In contrast, a study of exit poll data from the 1996 and 1998 House elections found little evidence of discrimination by voters.
• Evidence suggests that voters use a candidate’s race as a proxy for their ideology, with black candidates seen as more progressive. If white voters prefer more conservative candidates, the effect of a candidate’s race may be partially explained by these inferred ideological differences.
• Increasing minority representation is seen to have an impact on policy outcomes. In turn, this is more likely when minorities are elected by a large minority population and represent a substantial proportion of lawmakers. A study of state budgets over a 24-year period demonstrated that increased black representation in state legislatures has resulted in state legislatures giving greater priority to policy areas important to black elected officials.
• Evidence suggests that on moral issues, “minority lawmakers may be out of step with many of their constituents,” but the author suggests that additional research is necessary to explore why this could be the case.
• Overall, the study finds that minority legislators “are much more likely to support and initiate policies backed by minorities in the mass public; their election can mobilize minorities to participate in politics; their identity can shape the outcome of elections; their emergence has altered the coalitions of the major parties; and their presence in state legislatures encourages the adoption of policies favored by many minorities.”

In seeking to understand the continuing under-representation of minorities in politics, the author notes that “political incentives of Republicans coupled with the coalitional incentives of Democrats [could] lead the parties to support the maintenance of majority-minority districts in the states formerly covered by the [Voting Rights Act].” He suggests that more research is needed on how the presence of minority candidates can influence campaign issues, media coverage and endorsements.

Related research: A 2011 study published in the American Journal of Political Science, “The Jackie (and Jill) Robinson Effect: Why Do Congresswomen Outperform Congressmen?” explores the hypothesis that successful female candidates may need to be more ambitious or qualified than their male challengers to overcome gender bias, and that once in office they tend to outperform their male counterparts.

Keywords: Congress, race, African-American, Latino, Hispanic, inequality, discrimination