Over the past decades, the Census Bureau has increasingly relied on administrative data to help fulfill its core mission for the decennial census: to count every individual in the United States once, only once, and in the right place. A fair census ensures that every individual and every neighborhood is fairly counted, represented, and resourced. 

As the importance and role of administrative data have expanded in recent censuses, so have data sharing agreements between government agencies. However, stakeholders seeking to review and understand the terms and details of the data sharing are typically unable to do so. Data sharing agreements and related documents are often not publicly disclosed or, if available, not centrally compiled by government agencies.1 This lack of transparency raises questions about the tradeoffs between data utility and privacy risks. Increased transparency in data sharing agreements would allow stakeholders to better understand the benefits that administrative data provide and the potential privacy risks of data sharing for people and communities.

Data Sharing Agreements Enable the Acquisition & Use of Administrative Data To Improve Census Quality

Administrative data are collected by various levels of government and commercial entities that administer government programs and services, such as Supplemental Nutrition Assistance Program (SNAP), Medicaid, and U.S. Postal Service’s National Change of Address Program. The data are instrumental for the Census Bureau to meet its goals of providing quality statistical products, reducing burdens on the public to respond to surveys, and using government resources efficiently. The 2020 Census was the first to incorporate administrative data as a cornerstone of its design to improve survey quality, reduce costs, and lower respondent burden. Research indicates that the use of administrative data strengthened the 2020 Census operations and results—especially in light of the unprecedented challenges associated with the COVID-19 pandemic and extreme weather events. 

To acquire and utilize administrative data, the Census Bureau enters into data sharing agreements with the federal, state, and tribal government agencies that administer government programs and with the commercial entities that provide other services. When receiving the administrative data, the Bureau removes any personally identifiable information (PII) from the data and, as required by law, uses the acquired data only to produce and improve statistics. The Census Bureau is strictly prohibited by law from sharing identifiable information with other states or any governmental or law enforcement entities. 

Data Sharing Agreements Should Be Open to Public Review

Data sharing agreements between the Census Bureau and other agencies are not typically published or publicly accessible. Although the Freedom of Information Act (FOIA) allows access to data sharing agreements, it does not guarantee full disclosure of the contract terms. This is likely due to sensitive information in data sharing agreements, such as data handling procedures and security protocols. However, additional details and terms of the agreements—such as limits on data usage, length of usage and access, the parties involved in the data sharing, and steps taken to ensure data confidentiality—could feasibly be published or summarized without disclosing sensitive information. Increased public access to data sharing agreements would help stakeholders understand which agencies are sharing data, how personally identifiable information is protected and used, and what steps agencies such as the Census Bureau are taking to minimize and manage privacy risks. 

Public disclosure of data sharing agreements and related documents2 can empower stakeholders, enhance government accountability, and potentially influence policy decisions. In 2019, the Department of Homeland Security (DHS) published a Privacy Impact Assessment (PIA) ahead of the 2020 Census that detailed the agency’s data sharing agreement with the Census Bureau and provided an evaluation of potential privacy risks.3 This disclosure was of particular public interest and significance as the DHS had—for the first time—shared PII data about citizens and non-citizens with the Census Bureau, pursuant to the Trump Administration’s Executive Order 138800.4 With detailed information from the PIA, stakeholders scrutinized the DHS data sharing agreement and robustly challenged the Trump Administration’s broader effort to exclude undocumented immigrants and their families from the census numbers used to allocate congressional seats and redraw voting districts.5 In January 2021, the Biden-Harris Administration swiftly rescinded the executive order shortly after taking office.


Data sharing has significant advantages, such as improving the accuracy of census counts and helping ensure fair representation and resources for every person and every neighborhood. Data sharing also poses risks, including risks to individual privacy. Transparency can engender public trust in the data sharing process. As the Census Bureau seeks to balance utility and privacy, it is crucial to provide greater transparency around the agency’s data sharing practices.

1The Massive Data Institute has indexed a number of data sharing agreements and the specific data elements involved in the agreements. See https://mdi.georgetown.edu/resources-and-training/enabling-research/research-data-center/administrative-data-metadata/

2 Government agencies typically produce additional documents and evaluations, including Privacy Impact Assessments (PIAs), which provide analysis of the privacy implications of specific data sharing agreements. As with data sharing agreements, these documents and evaluations are not consistently available to the public and vary by the agency involved in the data sharing agreement.

3 The Department of Homeland Security (DHS) is one government agency that consistently publishes Privacy Impact Assessments (PIAs). For example, DHS’s collection on PIAs can be found here: “Privacy Impact Assessments (PIA) Collection.” Department of Homeland Security, retrieved 14 November 2023. Available at https://www.dhs.gov/publications-library/collections/privacy-impact-assessments-%28pia%29.

4 Executive Order 138800 Collecting Information About Citizenship Status in Connection with the Decennial Census (July 11, 2019) directed agencies to “promptly provide the Department the maximum assistance permissible, consistent with law, in determining the number of citizens, non-citizens, and illegal aliens in the country, including by providing any access that the Department may request to administrative records that may be useful in accomplishing that objective.”

5 For example, see “New York v. Trump, Complaint for Declarative and Injunctive Relief.” U.S. District Court for the Southern District of New York, retrieved 14 November 2023. Available at https://ag.ny.gov/sites/default/files/ny_v_trump_complaint.pdf.