Behind closed doors and without expert input, the Trump administration issued a major policy change to how census data is released. Data experts are concerned the result will be less reliable public data related to redistricting, natural disasters, the workforce, housing, and more.
On June 4, the Trump administration released an order,
Disclosure Avoidance for Statistical Products
, that forbids “any use of noise infusion” for statistical products. “Coarsening shall be the preferred category of Disclosure Avoidance methods for all statistical products,” the order states. “Suppression shall be permitted as a last resort, only to be used when coarsening is prohibited by law or would substantially defeat the accuracy or usability of a statistical product.” 
In statistical terms, noise infusion is a common and accepted technique for privacy protection when working with data: it creates “fuzz” or random values within a dataset, making the published statistics slightly different from the actual, sensitive data. Coarsening is the process of grouping and rounding data, or reporting it in ranges instead of potentially identifiable specifics. Suppression is what it sounds like: redacting information, replacing it with asterisks, or not releasing the data entirely. 
NPR’s Hansi Lo Wang
first reported on the policy change
and its implications. People who work with census data and statistical analysis are worried that limiting the ways the Census Bureau and the Bureau of Economic Analysis (BEA) can release data will severely limit what information ends up available to the public.
Data coming out of small communities and industries, especially, could be heavily affected by the change. “Because ‘coarsening’ (grouping, rounding, reporting in ranges) and suppression are the only not-prohibited tools named in the order, it means that to keep information safe, the Census Bureau and BEA need to group small things (like small communities or small business types) into larger ones, or

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