CLEVELAND (AP) ¿ California is questioning voting systems security based on research by a four-campus team that challenges the reliability of audit logs.

California found problems with the audit logs of Premier Elections Solutions, the maker of optical-scan and touch-screen systems used in 33 states.

The California secretary of state says Premier software does not keep track of ballot deletions. Some experts say the problem could violate voting system standards.

Premier says deletions would be accounted for in ballot canvasses and will be reflected in technology updates.

Allen, Texas-based Premier is a unit of North Canton, Ohio-based Diebold Inc.

Cleveland State University collaborated with researchers from Princeton, Stanford and the University of California on the 2007 review of California's voting machines.

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