Source of Income Laws Show No Big Effects for Renters Beyond Vouchers

Across the United States, a quiet experiment in fair housing law has been unfolding for decades. Source of income laws, now in force in more than 20 states and over 100 local jurisdictions, prohibit landlords from rejecting rental applicants simply because their income comes from public assistance, disability benefits, or other protected sources rather than wages. The stated goal is straightforward: a renter who can afford the apartment should not be turned away because the check arrives from a government agency instead of an employer. Yet while these statutes have spread rapidly, the evidence supporting them has been lopsided, focused almost entirely on one group of beneficiaries — holders of federal Housing Choice Vouchers — while leaving other protected renters largely unstudied.

A new study by economist Taylor Mackay of California State University, Fullerton, published in the Atlantic Economic Journal, offers the first systematic look at what these laws do for recipients of non-voucher categories of protected income, including people receiving Supplemental Security Income and welfare payments. The findings are striking in their restraint: across every outcome the study could measure, the estimated effects of source of income policies are uniformly close to zero. In nationally representative survey data spanning fifteen years, the laws do not appear to generate large, detectable aggregate changes in the housing circumstances of this population.

The technical challenge the study confronts is a familiar one in policy evaluation. Source of income laws were not adopted randomly; they passed in particular cities, counties, and states at particular times, often in places with stronger progressive political movements or more acute affordability concerns. A naive comparison between places with and without such laws could therefore confound the effect of the policies with pre-existing differences between those places. To address this, Mackay employs an event-study estimator drawn from the recent difference-in-differences literature, specifically building on methods developed by Clément de Chaisemartin and Xavier D’Haultfœuille, which are designed to handle policy adoptions that occur at different times across jurisdictions and to guard against biased comparisons when treatment effects vary over time or across groups.

The data underlying the analysis come from the American Community Survey, the Census Bureau’s large ongoing household survey, accessed through the IPUMS USA project. Mackay aggregates microdata from 2006 through 2021 to the level of Consistent Public Use Microdata Areas by year, creating geographic units whose boundaries remain stable even as official Census definitions change. This consistency matters: source of income laws are frequently adopted at the county or municipal level, and the ability to match those policies to stable geographic areas over time allows the study to capture far more policy variation than analyses relying on coarser geographic identifiers would permit.

Within those geographic units, the study identifies likely-affected renters — households reporting income from Supplemental Security Income or welfare programs, the non-voucher income categories most clearly protected by source of income statutes. The analysis then estimates intent-to-treat effects on four housing outcomes: residential mobility, gross rent, household size, and crowding. The intent-to-treat framing is deliberate. Because the surveys cannot observe which individual renters actually attempted to move or apply for housing after a law passed, the estimates capture the average effect of living in a jurisdiction covered by such a policy, an appropriately conservative measure of the laws’ real-world reach.

The results are notable for how tightly they cluster around zero. For residential mobility, the estimates are precise enough to rule out increases larger than 2 to 3 percentage points. Given a baseline annual mobility rate of roughly 22 percent among these renters, that means the study can exclude relative increases above about 10 to 13 percent. In other words, if source of income laws do help non-voucher protected-income recipients find or change housing, the aggregate effect is small enough to escape detection even in a study with substantial statistical power. Estimates for gross rent, household size, and crowding tell the same story: no large movements on any of the housing margins observable in the survey data.

Why might the laws matter so little for this group when prior research suggests they do help voucher holders? The study’s framing points to several plausible mechanisms rooted in how the rental market treats different income sources. Housing Choice Vouchers are a large, visible, federally administered subsidy that landlords can easily recognize and may distrust, so a legal mandate directly targets a well-documented form of discrimination. Field experiments and correspondence studies have long documented that landlords reject voucher holders at high rates, and earlier work by Lance Freeman and colleagues found that source of income protections increased voucher utilization and expanded access to less disadvantaged neighborhoods. Supplemental Security Income and welfare income, by contrast, may be less visible to landlords during the application process, or renters with such income may face binding constraints — affordability, credit history, screening criteria — that anti-discrimination law alone cannot overcome.

The study is careful about the limits of what its data can show. The American Community Survey does not record where a household lived before a move at the neighborhood level, so the analysis cannot test whether source of income policies changed the quality of destinations among renters who did move — the locational question that has motivated much of the voucher literature, including work by Ingrid Gould Ellen and colleagues on whether protections help recipients reach lower-poverty neighborhoods. Nor can the survey capture subtler outcomes such as application denials, search durations, or landlord behavior during leasing. It is possible that the laws improve the housing search experience for non-voucher recipients in ways that never register in annual mobility rates or rent payments. The estimates also concern the protected-income categories most clearly covered by the statutes; the study treats Social Security recipients separately in supplemental analyses, noting that households living mainly on retirement or other benefit income likely differ in composition and in their exposure to source-of-income discrimination.

For policymakers, the findings carry a sobering implication. Source of income laws are often promoted as a broad shield for all renters whose income comes from outside the labor market, and more than two decades of legislative activity reflects that ambition. The new evidence suggests that whatever benefits such laws deliver, they are unlikely to show up as large aggregate improvements in mobility, rent burdens, or crowding for SSI and welfare recipients. That does not necessarily mean the laws fail these renters — targeted benefits to a subset of applicants, reduced discrimination in principle, or improved search experiences could all be real while leaving population averages essentially unchanged. But it does mean that the strongest empirical case for the policies remains the voucher-focused literature, and that advocates hoping to demonstrate measurable gains for other protected groups will need better data, perhaps from field experiments or administrative records, to make it.

Methodologically, the study also demonstrates how far the policy-evaluation toolkit has come. By combining stable geographic panels built from Census microdata with modern event-study estimators that account for staggered policy adoption, Mackay is able to extract credible causal estimates from the messy patchwork of state and local lawmaking. The approach of measuring intent-to-treat effects on a nationally representative sample, and then reporting precisely how small the detectable effects are, offers a model for evaluating other anti-discrimination statutes whose benefits may be diffuse, targeted, or invisible in standard survey outcomes. As source of income laws continue to spread — and as housing affordability climbs the political agenda — this study sets an important baseline: for renters relying on Supplemental Security Income and welfare payments, the observable housing margins barely move, and any real effects of these laws must be sought somewhere the Census cannot yet see.

Subject of Research: The effects of source of income anti-discrimination laws on renters receiving non-voucher protected income such as Supplemental Security Income and welfare payments

Article Title: The Effect of Source of Income Policies on Recipients of Non-Voucher Categories of Protected Income

Article References: Mackay, T. (2026). The Effect of Source of Income Policies on Recipients of Non-Voucher Categories of Protected Income. Atlantic Economic Journal. https://doi.org/10.1007/s11293-026-09859-1

Image Credits: AI Generated

DOI: 10.1007/s11293-026-09859-1

Keywords: source of income laws, housing discrimination, rental housing, Supplemental Security Income, welfare payments, Housing Choice Vouchers, residential mobility, fair housing policy, American Community Survey, event-study estimator, housing economics, public assistance