Colorado became the first state in the nation after this month's election to complete a "risk-limiting" audit, according to the Secretary of State's Office.
Such an audit, ordered by the Colorado Legislature in 2009, is a procedure designed to provide statistical evidence that the election outcome is correct, and has a higher-than-normal probability of correcting a wrong outcome.
Risk-limiting audits require human beings to examine and verify more ballots in close races, and fewer ballots in races with wide margins.
"Colorado is a national leader in exploring innovative solutions for accessible, secure and auditable elections," said Matt Masterson, chairman of the U.S. Election Assistance Commission, who witnessed the audit. "Colorado's risk-limiting audit provided great insights into how to conduct more efficient and effective post-election audits. (The commission) is eager to share some of the lessons learned with election officials across America."
The commission awarded a grant to the state in 2011 to conduct a two-year pilot test of the system.
Though the Legislature required the audits to start in 2014, the 2009 law allowed the state to delay its implementation if ballot technology used by counties didn't allow for such audits. The state used the extra time to test various methods.
Mesa County was one of eight counties statewide that participated in a test run of the risk-limiting audit system in 2015.
"I think it's fair to say that both state and county election officials were a little anxious because this has never been done before," Secretary of State Wayne Williams said. "But it turned out to be an amazing success, and that's because our staff and our county clerks have done a phenomenal job. I am thankful for their hard work and dedication."
Colorado's use of risk-limiting audits was watched nationwide because of concerns about election fraud and hacking, particularly those raised during last year's general election. The procedure requires human eyes to compare paper ballots with digital tallies to see if results were tabulated correctly.
Since 2015, more than half of the states have enacted laws requiring similar audits, but no other state has as of yet used it, though some are close, according to an analysis by the Pew Charitable Trusts.