Audit Laws

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Audit Laws

State Summary

Under Arizona Rev. Stat. § 16-602, after each primary, special, general and presidential election, the county officer in charge of the election must conduct an audit of at least 2% of the precincts in that county, or two precincts, whichever is greater; plus at least 1% of early votes or 5,000 ballots, whichever is less. However, county political party chairs supply the election board workers to perform the audit, and the audit cannot proceed if they supply insufficient staff. The contests to be audited include up to five races: one statewide ballot measure (if applicable), one statewide office, one US Senate or US House of Representatives contest, one state legislative office, and the presidential race in a presidential election year. Audits results are to be reported prior to certification.

Unless otherwise specified, statutory references are to Arizona Rev. Stat. § 16-602.

Voting Systems Used

Arizona primarily uses hand marked paper ballots and optical scanners in polling places statewide, with ballot marking devices for accessibility. 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

The audit covers both regular ballots and early (mail) ballots, but not provisional and conditional provisional ballots.

For the precinct hand count, the officer in charge of elections must conduct a hand count of regular ballots from at least 2% of the precincts (or vote centers), or two precincts/vote centers, whichever is greater. Provisional and conditional provisional ballots are not included in the hand count. In a presidential preference election (PPE), the sample includes 2% of the polling places or vote centers, with no minimum.

The officer in charge of elections also is required to conduct a hand count of 1% of the total number of early ballots cast, or 5,000 early ballots, whichever is less. Counties may elect to audit a higher number of ballots at their discretion. According to the Arizona Election Procedure Manual, at least one batch of up to 400 early ballots from each central count machine used to tabulate early ballots and at least one accessible voting machine (if those machines independently tabulate votes) used during on-site early voting must be selected for the early ballot hand count process.


The audit statute only explicitly mentions the observation of the hand count audit by party representatives. In addition, political party observers may bring their own video equipment to record the audit. Arizona Rev. Stat. § 16-602(B). Further, the unofficial vote totals from all precincts must be made public before selecting the precincts to be hand counted, and Arizona Rev. Stat. § 16-602(I) requires that the results of the hand counts be made publicly available on the Secretary of State’s website. See also Arizona Election Procedure Manual.

Audit Counting Method

Ballots are audited by hand.

Type Of Audit Units

For in-person voting, the audit units are (in-person) precincts. For early (mail) voting, the audit units are batches of ballots tabulated together.

Contests & Issues Audited

The contests to be audited include up to five races: one statewide ballot measure (if applicable), one statewide office, one US Senate or US House of Representatives contest, one state legislative office, and the presidential race (in presidential election years). The particular contest is chosen at random, when applicable.

Addressing Discrepancies

If the audit count differs by more than a specified percentage (known as the “designated margin”) from the electronic tabulation of the same ballots (and a second hand count confirms the disparity), the hand count is expanded to include a total of twice the original number of precincts. If the expanded count again differs by more than the specified percentage, the hand count is extended to include the entire jurisdiction for that race within that county. Arizona Rev. Stat. § 16-602(C).

This specified percentage (“designated margin”) is determined by a seven-person vote count verification committee, whose members have expertise in “any two or more of the areas of advanced mathematics, statistics, random selection methods, systems operations or voting systems.” Arizona Rev. Stat. § 16-602(K).

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


The hand count begins within twenty-four hours after the closing of the polls and is completed before the canvassing of the election for that county. The results of the hand count must then be published on the Secretary of State’s website.

Binding On Official Outcomes

The audit can alter official totals but is binding on the outcome only when it leads to a full recount. “If the expanded hand count results in a difference in that race that is less than the designated margin when compared to the electronic tabulation of those same ballots, the electronic tabulation constitutes the official count for that race.” Arizona Rev. Stat. § 16-602(D).

Oversight & Conduct

The secretary of state oversees the audit, while the audit is conducted by both the county election officials and party representatives appointed by the county party chairperson.

Ballot Protection

The election board shall prepare a report and place it in the ballot box, in which the voted ballots have been placed. This box will then be sealed with a numbered seal and delivered promptly by two members of the election board of different political parties to the central counting place, which shall not be more than fifty miles from the polling place from which the ballots are delivered. The county officer in charge of elections shall retain custody of the ballots for purposes of performing any required hand counts and the officer shall provide for security for those ballots. For more information see, Arizona Rev. Stat. Ann. § 16-608.

Additional Targeted Samples

Arizona statute does not provide for targeted samples.


Arizona Rev. Stat. § 16-602: Audit statute

Arizona Rev. Stat. Ann. § 16-608: Ballot protection

Arizona Election Procedure Manual


Last reviewed: March 15, 2024

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