John Abowd

Abowd was a professor at Cornell when he became the Census Bureau's chief scientist in 2016. There he had the agency attack its own publications: from the tables released for the 2010 census, individual records could be reconstructed exactly for nearly half the population, and with commercial data a large share of them could be tied back to names. The traditional disclosure-avoidance methods, in other words, didn't hold.

The response was to publish the 2020 figures with calibrated noise under differential privacy. Demographers who lost small-area accuracy objected, and states went to court. It was the first time the techniques of Cynthia Dwork and colleagues were tested at such a politically charged scale, and the argument over the trade-off is still going.