Events Calendar

Theory Lunch

Speaker: Kobbi Nissim, Georgetown University

Talk Title: Legal Theorems of Privacy

Abstract: There are significant gaps between legal and technical thinking around data privacy. Technical standards such as k-anonymity and differential privacy are described using mathematical language and strive for mathematical rigor whereas legal standards are not rigorous from a mathematical point of view and often resort to concepts such as de-identification and anonymization which they only partially define. As a result, arguments about the adequacy of technical privacy measures for satisfying legal privacy often lack rigor, and their conclusions are uncertain. The uncertainty is exacerbated by a litany of successful privacy attacks on privacy measures thought to meet legal expectations but then shown to fall short of doing so.

We ask whether it is possible to introduce mathematical rigor into such analyses so as to make formal claims and prove "legal theorems" that technical privacy measures meet legal expectations. For that, we explore some of the gaps between these two very different approaches, and present initial strategies towards bridging these gaps. In particular, we focus on the concept of singling out from the EU's General Data Protection Regulation (GDPR). To capture this concept, we define a new type of privacy attack, predicate singling out, where an adversary finds a predicate matching exactly one row in a database with probability significantly better then a statistical baseline. We then argue that any data release mechanism that purports to "render anonymous" data under the GDPR should prevent predicate singling out. Hence, the concept has legal consequences as it can be used as a yardstick for arguing whether data release mechanisms meet the GDPR standard of data anonymization.


Biography: Professor Kobbi Nissim is a McDevitt Chair at the department of Computer Science, Georgetown University and affiliated with Georgetown Law. Nissim's work is focused on the mathematical formulation and understanding of privacy. His work from 2003 and 2004 with Dinur and Dwork initiated rigorous foundational research of privacy and in 2006 he introduced differential privacy with Dwork, McSherry and Smith. Nissim was awarded the Caspar Bowden Privacy for research in Privacy Enhancing Technology in 2019, the Gödel Prize in 2017, IACR TCC Test of Time Awards in 2016 and in 2018, and the ACM PODS Alberto O. Mendelzon Test-of-Time Award in 2013.

Host: Shaddin Dughmi

Location: 213

Audiences: Everyone Is Invited

Contact: Cherie Carter