The United States has a self-inflicted, widespread problem: concentrated poverty. Neighborhoods with concentrated poverty—defined as census tracts where the federal poverty rate is 40 percent or more—lack resources to provide quality schools, job opportunities, safe streets, and access to quality healthcare.

Nation’s Capital Broken down by Concentration of Wealth. Map by Urban Institute. Click the link to view an interactive map of the entire United States.

Research shows that this concentrated poverty is on the rise. Since the 1990s, trends reducing the proportion of poor families living in neighborhoods with concentrated poverty have reversed, and experts blame public policy as the source.

Exclusionary zoning is an oft-mentioned policy that keeps affordable housing out of neighborhoods through land use and building code requirements. It’s a legal practice that has been used for decades to keep lower-income people—disproportionately racial minorities—out of wealthy and middle-class neighborhoods across the country. It can have a damaging effect in that it prevents these low-income families from having access to the education and employment opportunities typically found in wealthier neighborhoods.

Where Did Exclusionary Zoning Come From?

Exclusionary zoning has existed in varying forms since the early decades of the twentieth century, when it was a vehicle for outright racial discrimination. Prior to the Supreme Court’s Buchanan v. Warley decision in 1917, city zoning ordinances across the country legally forbade minorities from occupying blocks where the majority of residents were white. Buchanan v. Warley was the first in a series of cases and actions by the federal government that limited legal housing discrimination and culminated in the 1968 Fair Housing Act.

…the Fair Housing Act provides a loophole for discrimination that confines low-income people to certain neighborhoods by systematically preventing them…

The Fair Housing Act prohibits discrimination based on race, color, national origin, religion, sex, ability, and familial status. Notably, however, it does not prohibit class-based discrimination. As a result, the Fair Housing Act provides a loophole for discrimination that confines low-income people to certain neighborhoods by systematically preventing them—through economic tactics such as minimum lot size and other expensive requirements—from moving into areas of with access to opportunity.

In 1977, the Supreme Court’s decision in Village of Arlington Heights v. Metropolitan Housing Development Corp. institutionalized that loophole by asserting that exclusionary zoning is not unconstitutional. While not as overt, contemporary exclusionary zoning contributes to the same patterns of segregation as pre-Buchanan v. Warley policies. Because racial minorities are much more likely to have lower incomes, class-based discrimination tends to have a disparate impact on them, paralleling the racial discrimination of the past. In other words, the class-based discrimination embodied in today’s exclusionary zoning is, in its outcome, de facto racial discrimination.

What Does Exclusionary Zoning Look Like?

Traditionally, exclusionary zoning policies have kept poor, central city residents out of suburbs with minimum lot size requirements, single residence per lot requirements, minimum square footage requirements, and costly building codes. Together, these requirements make it difficult to build multi-family rental units that would allow lower-income residents to live in wealthy suburban developments with access to quality schools and employment. In addition, large lot size requirements reduce the supply of available land, drive up housing costs, and further keep out low-income families.

Recently, use of exclusionary zoning has expanded into the urban core as wealthy and largely white families move back into cities. Within cities, policies like building height limits and school district lines increase property values and force low-income families into areas of concentrated poverty. Still, the effects of urban exclusionary zoning pale in comparison to the massive movement to the suburbs since the ’70s.

What Are the Impacts of Exclusionary Zoning?

Exclusionary zoning promotes income segregation by creating areas of concentrated poverty and concentrated wealth. As Century Foundation fellow Paul Jargowsky explains in his report “Architecture of Segregation,” the prevalence of concentrated poverty has increased since the turn of the century, and its effects are detrimental.

In 2000, 10.3 percent of the poor lived in high-poverty neighborhoods. By 2013, this proportion increased to 14.4 percent. The raw numbers have increased as well. In 2000, about 7.2 million Americans lived in high-poverty neighborhoods. By 2013, that number had nearly doubled to 13.8 million.

One-in-four black Americans and one-in-six Hispanic-Americans living in poverty reside in high-poverty neighborhoods.

These changes have disproportionately impacted minorities. One-in-four black Americans and one-in-six Hispanic-Americans living in poverty reside in high-poverty neighborhoods. Only one-in-thirteen poor white Americans lives in high-poverty neighborhoods.

High-poverty areas are marked by limited employment opportunities, underperforming schools, high crime rates, and few recreational spaces, making it nearly impossible for struggling families to achieve social mobility. By preventing families from moving into areas of opportunity, exclusionary zoning perpetuates the cycle of poverty.

What Are Perceived Justifications for Exclusionary Zoning?

Proponents of exclusionary zoning cite declining property values as the primary reason to keep low-income people out of their neighborhoods. The research around property values is murky. On the one hand, research shows that land-use diversity actually increases property values. On the other hand, the same research shows that racial diversity tends to decrease them.

Still, evidence about the impact of racial diversity on property values often reveals that these findings have been fueled by underlying and outdated fears. For decades, the Federal Housing Administration and National Association of Real Estate Boards included provisions in their code of ethics and underwriting manuals that explicitly described racial minorities as “detrimental to property values in that neighborhood.” Unfortunately, if white sellers, renters, lenders, and buyers perceive minority status as detrimental to property values—as they have been conditioned—they will be less willing to pay to live in racially diverse neighborhoods, creating a self-fulfilling prophecy of segregation.

What Has Been Done To Stop Exclusionary Zoning?

Fair housing advocates have long recognized that exclusionary zoning perpetuates patterns of racial and income-based segregation. In 1969, just one year after the Fair Housing Act was passed, then U.S. Secretary of Housing and Urban Development George Romney attempted to outlaw exclusionary zoning with the Open Communities initiative. President Nixon rejected his proposal and Secretary Romney eventually resigned from his post.

Since then, some local governments and courts have implemented policies that combat exclusionary zoning in municipalities across the country. For example, in 1974, Montgomery County, Maryland passed legislation that requires developers to set aside 15 percent of units to sell or rent below market value. This policy has created over 11,000 units of affordable housing in Montgomery County, an otherwise wealthy and suburban area. Additionally, the next year, the New Jersey Supreme Court decided in the Mount Laurel decision that every town in the state must provide its “fair share” of the region’s affordable housing.

At the federal level, in June 2015, the U.S. Supreme Court upheld the legitimacy of disparate impact complaints in cases of housing discrimination in the 5-4 decision of Texas Department of Housing and Community Affairs v. Inclusive Communities Project, Inc. In the majority opinion, Justice Anthony Kennedy asserted that the removal of exclusionary zoning lay at the “heartland” of the Court’s decision.

Despite these efforts, in most parts of the United States, exclusionary zoning makes high opportunity neighborhoods inaccessible to lower income Americans.