Roughly 600,000 prisoners will return to their communities by the end of this year, but if the past is any indicator, as many as 60 percent of those individuals will be convicted of a new offense by 2024. Many factors contribute to a person’s propensity to reoffend, including employment, family ties, and behavioral health treatment. But studies show that another factor, access to stable housing, is just as important to ensure successful reentry.

Due to data limitations, randomized control trials, the gold standard for research, are few and far between in criminal justice literature. But several evaluations have found that access to housing, particularly for those already at risk of reoffending, is key to reducing recidivism. Most notably, one evaluation in Washington state found that a housing program significantly reduced new convictions, and that periods of homelessness significantly increased new convictions.

Regrettably, formerly incarcerated people are almost 10 times more likely to be homeless than the general public. And the number of justice-involved individuals who experience housing insecurity (a measure that includes those living in marginal housing, e.g. hotels) is nearly three times that. The problem is worse in large, urban areas. In New York City, for example, more than 54 percent of people released from prison moved straight into the city’s shelter system in 2017.

To address the housing insecurity of people leaving prison, justice reformers usually advocate a handful of proposals, like increased federal funding for Section 8 vouchers, direct subsidies to returning citizens, mandates for up-zoning proposals to include affordable housing options, and “ban the box” proposals for public housing authorities and private landlords alike. Such proposals may have merit, to be sure, but few of them would address the underlying issue: land-use zoning laws that restrict housing supply.

Housing for disadvantaged groups has been a chronic pressure in municipalities everywhere. Social housing is one solution, but it has struggled to align individual needs with political constraints. Rather, most disadvantaged groups rely on low-cost rentals, whether legally or informally permitted.

To ensure there are enough low-cost units on the market to house the formerly incarcerated as they return to their communities, towns and cities need to permit construction of low-cost housing typologies. Single-room-occupancy (SRO) buildings, boarding houses, and group homes are cheap to build and maintain. Shared kitchens and bathrooms save space, and are a boon to those simply looking for a place to rest their heads as they settle back into society. But many places don’t allow these housing archetypes at all. Boarding-house bans are common in single-family zones nationwide. Those that do allow shared-facility buildings often restrict their use in other ways.

One particularly burdensome rule for the formerly incarcerated is maximum occupancy requirements. The typical occupancy maximum limits the number of unrelated individuals who may share a home. This prevents landlords from even subdividing existing homes into shared-facility buildings, to say nothing of purpose-built single-room-occupancy rentals. Legalizing these arrangements would provide more options for those leaving jail and prison.

But access to small, affordable apartments is not the only land-use issue preventing the formerly incarcerated from successfully reentering society. Single-use zoning separates residential areas from job-dense shopping and industrial parts of town. When zoning rules lengthen commutes, formerly incarcerated individuals who lack access to cars have problems accessing jobs and social services. But mixed-use zones, which allow the co-mingling of businesses, civic space, and residential units, create areas where it’s viable to live and work without the expenses of automobile ownership.

States and localities that recognize the formerly incarcerated’s housing issues have well-understood policy mechanisms to address the underlying problems. Legalizing SRO buildings and repealing occupancy maximums would allow the construction of new, low-cost buildings and legalize subdivision of existing homes into affordable rentals. Shifting from single-use to mixed-use zones would ease the problems faced by the formerly incarcerated when they are forced to rely on transit. Better still, these laws would increase competition among landlords at the low end of the rental housing market. In doing so, landlords’ power to turn away individuals based on criminal history would decline.

Those who have recently left the incarceration system face enough challenges. Housing doesn’t need to be one of them. Policymakers have plenty of tools to create an ample supply of low-cost housing for vulnerable populations. But doing so has political costs. We think the benefits are worth it, both for the formerly incarcerated and society at large. But we’re not local politicians. This choice is theirs.

This piece was co-authored with Jonathan Haggerty (@JHaggrid), manager of criminal justice and civil liberties at the R Street Institute.