Audit Laws

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Audit Laws

State Summary

Under C.R.S. §1-7-515, following each primary, general, coordinated, or congressional district vacancy election, each county shall make use of a risk-limiting audit. Races to be audited shall be selected in accordance with procedures established by the Secretary of State, and all contested races are eligible for such selection. The audit is to be completed before the official election outcomes are finalized. The RLA will continue until the risk limit for the target contests is met or until a full hand count results.

Unless otherwise specified, statutory references are to Election Rules 8CCR 1505-1, Rule 25.

Voting Systems Used

Colorado primarily uses hand marked paper ballots (usually with optical scanners) in polling places statewide, with ballot marking devices for accessibility. One county hand counts in lieu of using optical scanners. For the most up to date information please visit Verified Voting’s Verifier.

For an explanation on the types of voting equipment used, click here.

Audit Comprehensiveness

Colorado utilizes a risk-limiting audit with procedures and contest selections to be established by the Secretary of State, although all contested races are eligible. See, C.R.S. § 1-7-515 (2)(a)

Ballots included in the RLA: all in-person and accepted mail ballots, and any accepted provisional and property owner ballots that the county opts to include on the ninth day after election day. See, Rule 25.1.8. One county that hand-counts its ballots is exempted from the audit.


At least two canvass board members must observe at least the first round of the RLA. The designated election official, members of his or her staff, and other duly appointed election judges, may assist with the risk-limiting audit. Members of the public (watchers) are allowed to observe the audit. See, Election Rules [8 CCR 1505-1] 8.10.2. Audit results are posted on the Secretary of State’s official website.

Audit Counting Method

Under Rule 25 (and consistent with the statutory requirement for a risk-limiting audit), audit boards manually examine the ballot cards randomly selected for the audit.

Type Of Audit Units

Colorado audits individual ballots. As of 2020, all counties that participate in the audit must conduct a ballot comparison audit (although Rule 25 provides alternatives for counties that are determined to be unable to do so); one county that hand-counts its ballots is exempted from the audit.

Contests & Issues Audited

The Secretary of State will select, as “target contests,” at least one statewide contest (or other contests if there is no statewide contest), and for each county at least one other contest, taking into account criteria listed in Rule 25 at 25.2.2(j).

In a primary election, the Secretary of State will select at least one countywide contest of each major political party in each county. The risk limit is binding on these target contests. Moreover, in counties that conduct comparison audits (as of 2020, all participating counties), the audit board must examine each randomly selected ballot card and report the voter selections in all contests that appear on the ballot card.

Addressing Discrepancies

If the board discovers discrepancies during the post-election audit, the board must: (1) confirm that the manual count of the votes contained in the audited ballots is correct; (2) confirm that the manual count of the votes contained in the audited ballots properly reflects over-votes, stray marks on the ballot, and other indications of voter intent; (3) determine whether any discrepancy is attributable to a damaged ballot; and (4) take any other action necessary in accordance with the canvass board’s powers.

The RLA will continue until the risk limit for the target contests is met or until a full hand count results.

For recount laws, see Citizens for Election Integrity Minnesota website.


The risk-limiting audit (or any resulting recount) must be completed before results are finalized, even if certification is delayed to accomplish this. The Secretary of State selects the target contests to be audited by the Friday after election day. The random seed is established and the audit sample generated in a public meeting on the tenth day after election day. Each county audit board must complete its report by the day before the canvass deadline.

Binding On Official Outcomes

The audit is to be completed before certification. If the audit leads to a recount, the results of the recount are binding. See, C.R.S. §1-7-514 and C.R.S. §1-7-515

Oversight & Conduct

The Secretary of State oversees and regulates the audit by establishing rules to administer and enforce audit laws. For every election, the Secretary of State initiates a manual random audit to be conducted by each county- unless an alternative method for a particular county is approved that is based on a proven statistical sampling plan and will achieve a higher level of statistical confidence. County officials and audit boards then conduct the audit.

Ballot Protection

The governing body of each political subdivision using paper ballots or electronic vote counting equipment shall provide each polling location at least one strongly constructed ballot box so as to prevent tampering. See also, C.R.S. § 1-7-802. The designated election official shall be responsible for the preservation of any election records for a period of at least twenty-five (25) months after the election or until time has expired for which the record would be needed in any contest proceedings, whichever is later. For more information see, C.R.S. § 1-5-502.

Additional Targeted Samples

Colorado statute does not provide for targeted samples. However, Rule 25 provides that the Secretary of State “will review the audit board’s report and may direct the county clerk to conduct additional audit rounds, a random audit, a full hand count, or other action.” Therefore, other action could comprise targeted hand counts.

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