The Census Bureau released a proposal for new procedures to ensure the confidentiality of public use data, using a strategy called differential privacy. This comment letter raises concerns that the proposed new disclosure avoidance system, which relies on injecting noise with formal privacy rules, would significantly reduce or even eliminate the usability of public use microdata. IMPACT and researchers across the country rely on these data to understand phenomena at geographies or aggregations that are not routinely published in Census or ACS summary tables. The flexibility provided by the microdata allows IMPACT to be responsive to unique program and policy questions and help decision-makers in Chicago and Illinois understand how to craft policies and distribute resources in a way that meets the needs of particular populations.
You can also view the letter via the regulations.gov website: https://www.regulations.gov/document?D=USBC-2018-0009-0648