Many Colorado voting machines are decertified, throwing presidential votes in disarray

Colorado's secretary of state has declared many of the state's electronic voting machines to be unreliable, a move that could leave the looming presidential election here in disarray.

Secretary of State Mike Coffman decertified three of the four equipment manufacturers allowed in the state. That affects six of Colorado's 10 most populous counties.

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The four systems are manufactured by Hart InterCivic, Premier Election Solutions — formerly known as Diebold Election Systems — Sequoia Voting Systems, and Election Systems and Software. Only Premier Election Solutions had all its equipment pass the recertification.

Two kinds of electronic voting machines made by Sequoia Voting Systems that are used in Denver, Arapahoe, Pueblo and Elbert counties were decertified because of "a variety of security risk factors."

Machines that scan and count ballots made by Hart InterCivic failed because "they could not accurately count ballots." Hart equipment is used in Boulder, Douglas and more than 40 other counties.

And both optical scanning devices and electronic voting machines made by Election Systems and Software did not pass muster, Coffman said. ES&S is used by Jefferson and Mesa counties.