Pima County Recorder F. Ann Rodriguez has announced an overhaul of a program that creates voter rosters as well as improvements to her office's quality-control systems.
The move comes as the office concludes its investigation into the cause of the large number of provisional ballots - more than 27,000 - issued for the Nov. 6 election.
Provisional ballots are sealed in envelopes that voters sign at the polling place, requiring verification and counting after Election Day and contributing to delays in race results.
Rodriguez said her office's errors led to 5 percent of those provisionals, with the rest resulting from voters not following directions.
There is no way to account for the number of voters who showed up at a polling place and went home because their name could not be found on the voter roster.
Rodriguez accepted responsibility on behalf of her staff, the news release said.
"It is unacceptable to the Recorder that a roster printing error should require even one voter to vote by provisional ballot," it said.
"Staff at the Recorder's Office should have detected the computer malfunction prior to releasing the signature rosters as a public document."
The investigation found two issues related to part of the program that generates the voter rosters used at polling places. The roster table was not being refreshed as intended.
First-time voters who registered on or just before the deadline were listed out of order on the rosters, the news release said.
Close to 1,100 names were affected, but poll workers were able to find 861 of the names and allow those voters to use a regular ballot, the release said. Poll workers couldn't find more than 200 of those names, resulting in provisional ballots being issued.
The names of voters who changed their address in October appeared on the roster at a previous polling site, rather than at the location matching their new address, the release said. That error meant that 1,057 voters were required to cast a provisional ballot.
To prevent the malfunctions from reoccurring, the program generating the rosters will be redesigned and written in a more modern programming language, the release said.
On StarNet: For results and totals of the 2012 election, go to azstarnet.com/elections
Contact reporter Carli Brosseau at email@example.com or 573-4197. On Twitter @carlibrosseau.