ACLU research suggests that California’s vaccine distribution plan may leave more than 2 million vulnerable residents without additional supply

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SAN FRANCISCO – The ACLU Foundation of Northern California is calling on state officials to ensure that its equity-focused COVID-19 vaccine distribution plan won’t leave some of California’s most vulnerable communities behind. An ACLU analysis suggests that the California Department of Public Health’s vaccine-distribution algorithm may leave more than 2 million vulnerable Californians—many of them from Black and Latinx communities—without additional supply, despite the state’s core goal of equity in vaccine distribution.

In a blog published on the ACLU’s website, Technology and Civil Liberties Attorney Jacob Snow writes that the state’s distribution algorithm, which has reportedly been delivering an additional 20% of vaccine doses to certain ZIP codes with worse health and quality of life outcomes, could be erasing smaller underserved neighborhoods from the state’s priority list by virtue of the fact that those neighborhoods lie outside of priority ZIP codes.

To advance the goal of equity in vaccine distribution, the state decided in January to use the “Healthy Places Index”—a metric that assigns scores to communities across California according to a variety of health and economic measures—in order to identify areas where additional vaccine supply would be necessary. A few weeks later, the state announced that Blue Shield would build an algorithm allocating vaccines based on ZIP codes with low health and economic scores on the Healthy Places Index.

But not all communities in need of the vaccine are in the state’s priority ZIP codes, writes Snow. The problem lies in the fact that many ZIP codes are large enough to contain both low-income and wealthy communities, such as downtown San Francisco or Los Angeles. The Index was built using detailed information associated with smaller areas called census tracts—which, unlike ZIP codes, are specifically designed for making place-based socioeconomic comparisons—in order to identify communities with the lowest health outcomes in the state.

The interactive map in the blog post demonstrates the impact of this algorithm on communities across the state. The map’s red areas depict the census tracts in the least healthy 25% of the Healthy Places Index that fall outside of the prioritized ZIP codes (which are shown in blue), and that may not be receiving additional vaccine supply.

Those areas potentially left behind are disproportionately communities of color. According to 2010 census data, statewide, Latinx people make up approximately 38% of California’s population, but Latinx people make up 53% of the population in the census tracts that are possibly being omitted from the state’s equity focus. The same is true of Black populations, making up about 6% statewide but 8% of the census tracts potentially left behind.

Snow writes that, while the state may have compelling reason to use ZIP codes rather than census tracts, the state must be transparent about the consequences of that decision: “Technology can alleviate harm, but it can also exacerbate existing inequality. The research results we release today are meant to advance California towards both transparency and equity.”

The ACLU Foundation of Northern California is calling on the California Department of Public Health to review the 469 census tracts identified through its analysis and to explain how they will account for the health needs of those communities.

“Algorithmic systems can cloak human decisions in a guise of objectivity, but every decision made by a computer was, at bottom, made by the people who designed, built, and deployed those systems,” Snow said. “When algorithmic or other technical systems are part of public policy, the public has a right to know what information is being used and why, how they work, and what the consequences will be for every person touched by the system.”

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