Avi Rubin
Johns Hopkins professor whose 2003 teardown of Diebold voting machines made election technology a security issue in the US.
In the summer of 2003 the source code for Diebold's AccuVote-TS turned up on an open FTP server. Rubin, Tadayoshi Kohno, Adam Stubblefield and Dan Wallach analysed it and found hard-coded keys, weak or absent encryption, and smart cards anyone could forge. The report triggered state reviews and fed directly into the push for voter-verified paper ballots.
Rubin went on to lead ACCURATE, an NSF-funded research centre on voting technology, and wrote Brave New Ballot (2006). He is also co-author of the second edition of Firewalls and Internet Security (2003), alongside Bill Cheswick and Steve Bellovin.