"While the evidence in this case properly gave rise to concerns that were appropriately address to law enforcement, the investigation did not reveal any evidence to support ... criminal prosecution," the office said Monday in an investigative report.

In series of emails, the secretary of state's office, then run by Kemp, said led it to accuse the Georgia Democratic Party of hacking its voter registration system. The emails refer to findings by a voter who said he had discovered potential vulnerabilities in the state's voter information page and its online registration system.

The voter took his concerns to the Georgia Democratic Party's voter protection hotline to alert authorities, according to his lawyer, David Cross. At the time, Cross told CNN that the voter was not affiliated with any political party and did not want to speak to any media. He also said the voter has some software background but is not a hacker.

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