The state said Wednesday it will continue reviewing its voting system security despite an admission by a researcher who was critical of Georgia's touch-screen machines that he had a conflict of interest.

The study released last month found that the Diebold Election Systems machines used in several states, including Georgia, are vulnerable to tampering by unscrupulous voters, poll workers, software developers and "even janitors." The company is based in North Canton, Ohio.

On Tuesday, Avi Rubin, a Johns Hopkins University instructor and lead researcher on the study, said he failed to disclose his financial ties to a Diebold competitor, raising questions about the study's conclusions.

...

Rubin said in a statement Tuesday he had stock options in Diebold competitor VoteHere Inc. and was a member of the company's technical advisory board. He said he would resign from the board and give up the stock options.

Diebold officials said they were "shocked and disappointed" by Rubin's admissions.

"Diebold Election Systems has consistently questioned the conclusions drawn by the Johns Hopkins-issued report," the company said in a statement Tuesday. "It is now clear, by Mr. Rubin's own admission, that questions of bias must be considered."