Expert says Michigan's 'optical scan' voting system is secure

Alex Halderman - the University of Michigan professor who successfully hacked into a test version of the Washington, D.C.'s computer voting system - says Michigan voters should not be worried that their votes will be tampered with on Tuesday's election. 

Haldermn says most of Michigan’s polling places use optical scanners: voters fill out paper ballots that get scanned into a computer.

Halderman says optical scanners offer a pretty high degree of security because of the paper trail and "anywhere where we’re not using paper in the voting process, or we’re not using it properly, [is] a cause for concern."

He says Michigan's voting system isn't perfect, though. He says election officials don’t do routine audits to make sure that the paper ballots are scanning properly, but that he's "hoping to convince them to do that in future elections."