Hackers broke into electoral systems in at least 21 states -- but government agencies have conducted almost no investigations into the breaches.
Voter registration and election databases and other critical election services operated by at least three companies were hacked during the 2016 election, but little is known about who broke into the systems or how, reported the New York Times.
Many voters in North Carolina were told early on Election Day that they weren't eligible to cast ballots and turned away, even after showing their current registration cards, and others were incorrectly told they had already voted.
Most of those complaints came from Democratic-leaning precincts in Durham, and the problems involved electronic voting equipment that has replaced paper voter rolls used to verify identities and registration status.
"It felt like tampering, or some kind of cyberattack," said Susan Greenhalgh, a troubleshooter for a nonpartisan election monitoring group.
She knew that VR Systems, which provides Durham's software, had been previously breached by Russian hackers months before the election -- but it's not clear what happened Nov. 8.
Despite the widespread problem, a record number of votes were cast in Durham, which overwhelmingly supported Hillary Clinton, following a recent trend there in favor of Democratic presidential candidates.
Similar problems surfaced in Virginia, Georgia and Arizona, the Times reported.
“We don’t know if any of the problems were an accident, or the random problems you get with computer systems, or whether it was a local hacker, or actual malfeasance by a sovereign nation-state,” said Michael Daniel, cybersecurity coordinator under former President Barack Obama. “If you really want to know what happened, you’d have to do a lot of forensics, a lot of research and investigation, and you may not find out even then.”
Government officials said they intentionally did not address back-end security because they feared disrupting the election process, and the federal government has not been willing to intrude in voting -- which is overseen by cash-strapped states.
Intelligence officials have said they found no evidence that Russian hackers altered the vote count, but those agencies are prohibited by law from performing a broad examination into possible foreign meddling.
Congressional and special counsel investigations into the Trump campaign's alleged ties to Russia have not focused on the possibility of hackers breaching election systems.
Election security experts admit an investigation of the possible hacking would be costly and difficult -- but they said it was necessary, because any successful effort would likely be repeated.
“We still don’t know if Russian hackers did this,” Greenhalgh said. “But we still don’t know that they didn’t.”