The Chicago Board of Elections distributed computer discs to aldermanic campaigns in 2003 which contained the Social Security numbers of more than a million voters. The voter information on the discs also included names, addresses, and birthdates.

Since this inceident, more discs containing Social Secuirty information have been distributed. Officials said that there was no evidence of identity theft from the incidents, but the Board of Elections will notify voters that their data has been compromised.

Voter records have now been changed to only include the last four digits of Social Security numbers.