By now you’ve probably heard the news that Los Angeles Clippers owner Donald Sterling has been banned for life from the NBA for his racist rant. But as numerous outlets have noted, this isn’t the first time Sterling has come under fire for bigoted views and prejudicial actions.

As Dave Zirin reports for The Nation, Sterling has repeatedly faced allegations of housing discrimination from his tenants (he owns property across Southern California). For instance, back in 2004, Elisheba Sabi, an immigrant from Iran who held a voucher for low-income rental assistance, sued Sterling for refusing to rent to her.

In the end, the court sided with Sterling. While California laws prohibit discrimination based on a tenant’s income, the court ruled that it did not cover Section 8 vouchers.

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Housing discrimination was supposed to go away with the passage of the Fair Housing Act in 1968. But as Sterling’s banishment from the NBA reminds us, the fight to end discrimination continues today. We’ve made some progress, but there’s still a gaping hole in America’s fair housing laws – one that leaves renters like Sabi vulnerable to discrimination.

You might assume that people participating in a federal housing program would have federal protection from blatant discrimination in the housing market. But surprisingly, recipients of federal rental assistance are not covered under the Fair Housing Act. That means that people receiving Section 8 Housing Choice Vouchers are not considered a protected group, like racial minorities or people with disabilities are under federal fair housing laws. That policy oversight leaves millions of low-income households vulnerable to unfair treatment in the rental market.

How? Well, let’s start with why this program matters. The fight for equality of opportunity starts at home—where we live shapes the education we receive, the safety we feel in our neighborhoods, the jobs we’re able to find and take, and the community resources we’re able to enjoy. Policymakers (prodded along by advocates and community organizers) have worked to improve the situation in important, measurable ways, but we haven’t eliminated housing discrimination entirely.

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Here’s what it looks like on the ground: Low-income families that receive housing assistance through the Section 8 Housing Choice Voucher program (frequently known as “Section 8” or “vouchers”) are able to rent homes in the private rental market by essentially splitting the cost of rent with the housing authority—the families contribute 30% of their income to rent and the housing authority makes up the difference for a fair market rent.  This is supposed to give them more housing options.

But landlords often don’t like the extra paperwork, and use that hassle as an excuse to avoid these tenants. Once a family qualifies for and receives a voucher, they’re facing a race against the clock: If they can’t find a place to accept their voucher in a set window of time, they’ll lose the subsidy altogether and be back to square one.

This isn’t just theory: At a recent meeting in northern California that I attended as a policy analyst for New America Foundation, a Washington DC-based think tank, employees of several housing agencies talked about how hard it is for their voucher holders to find housing.Sure, California is a tough rental market, but staff noted that many landlords go out of their way to avoid Section 8 tenants because they don’t want to deal with the paperwork required to participate or they perceive tenants to be irresponsible or hard to work with.

This can mean spelling out “No Section 8” in a housing ad, refusing to return a prospective renter’s phone calls, or claiming certain units aren’t available for rent. In some cases, landlords rely on race- or class-based stereotypes to justify why they don’t want Section 8 tenants. As one staff member put it, landlords tell the housing authority: “Those people don’t belong here. You’re bringing in an element we’re not used to.”

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The National Fair Housing Alliance reported last year that only 13 states offer protection to voucher holders against this type of discrimination. California is not among them, though a few California counties have introduced local ordinances to prohibit singling out voucher holders. But with no federal protection, many landlords across the U.S. are free to turn away qualified tenants with vouchers— without risking the financial and legal repercussions they would if they turned down a person with a disability or because of racial bias.

Mounting evidence suggests that widespread inaction on this issue has paved the way for unequal treatment of low-income renters with vouchers. The impact? A family already struggling to make ends meet can’t freely choose where they want to live and it undermines the effectiveness of a program designed to promote stability and improve housing options.

The first step is a clear policy that protects voucher holders under federal fair housing laws—complete with concrete penalties to aid in enforcement efforts.

This change might not end all discrimination by landlords (more on that in another column) but it would send them a strong message that the federal government is watching.  Since it’s a federal program in the first place, this solution seems overdue.

Hannah Emple is a policy analyst at New America Foundation. Her research focuses on U.S. housing policy, racial wealth disparities, and strategies to improve public benefits programs to promote the financial stability of low- and middle-income families.