Among the polls we found on the World Wide Web in November 1995 were VOTELINK, a Web site that features weekly votes on a variety of local, national, and international issues (http://www.votelink.com/votelink/ns/home.htm); Presidential CyberPoll, a Web site that polls visitors on their preferred Presidential candidate (http://www.rtis.com/nat/pol/cyberpoll/); Interactive@ValueLine, a Web site that polls visitors on their preferred Presidential candidate, predictions about the OJ trial, and other topics (http://www.dfw.net/1#1alans/inter/); and Geertt's Pollpage, a Web page that asks visitors to name their favorite actress, handsomest man, and other celebrity preferences (http://www.stack.urc.tue.nl/2#2geertt/). None of these sites claimed to offer any privacy protection. Two of them claimed that they would only count one vote from each voter.

In the Sensus system, there is no difference between an election and a survey. Therefore, throughout this paper the terms poll, election, and survey will be used interchangeably. Likewise, the term ballot will refer to both survey forms and ballots and the term voter will refer to both voters and survey respondents.

Slessenger [21] reports that voter privacy is not a requirement in the United Kingdom, where voter identification numbers and ballot numbers are recorded together.

Benaloh and Tuinstra [1] explain:
There are reports that in some small Italian villages, the voting system employed allows voters to list their votes in any order. Political bosses are said to assign different permutations of their preferred candidates to each voter. If a particular permutation fails to appear when the votes are counted, a boss can assume that the voter to which that permutation was assigned did not vote ``properly'', and reprisals can be taken.

The Sensus polling protocol uses blind signatures to preserve privacy and democracy simultaneously. First introduced by Chaum [4], blind signatures allow a document to be signed without revealing its contents. The effect is similar to placing a document and a sheet of carbon paper inside an envelope. If somebody signs the outside of the envelope, they also sign the document on the inside of the envelope. The signature remains attached to the document, even when it is removed from the envelope.

We have implemented a prototype ballot authoring tool called Ballot Palette. This module was implemented using C and the XView tool kit. It provides a graphical representation of a ballot and allows users to edit ballots by dragging icons with a mouse. Ballot Palette then produces BLT code for the created ballot.

Lorrie Faith Cranor
Sun Nov 5 20:54:12 CST 1995