Audit Laws

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Audit Laws

State Summary

Signed into law in 1965, California’s audit law calls for every contest and ballot issue on the ballot to be audited by means of a hand count of 1% of the precincts in each jurisdiction during the official canvass. See Cal. Elec. Code, div. 5 § 336.5, “One Percent Manual Tally” and Cal. Elec. Code, div. 15, § 15360. Since 2017, the statute exempts ballots not counted in the “semifinal official canvass,” thus potentially excluding many mail and provisional ballots.

Pursuant to Cal. Elec. Code, div. 15 § 15367(a)(1), commencing with the statewide primary election held on March 3, 2020, the elections official conducting an election was permitted to conduct a risk-limiting audit for one or more contest(s) in place of the one percent manual tally of those contests. The risk-limiting audit pilot program expired on January 1, 2023. See A.B. 2400, 2019–2020 Leg. (Cal. 2020).

Unless otherwise noted, California Election Code § 336.5 and § 15360 are used to provide audit information.

Voting Systems Used

Most California counties primarily use hand marked paper ballots and optical scanners in polling places, with ballot marking devices for accessibility. Los Angeles County and Riverside County use ballot marking devices for all polling place voters. 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

AB 840 (2017) revised California’s 1% manual tally to exempt ballots not counted in the “semifinal official canvass,” which must be completed by the Thursday after election day. Thus, large numbers of mail and provisional ballots potentially are excluded from the audit.

Effective August 2020, county election officials may choose to conduct risk-limiting audits of any contest(s) fully contained within the county in lieu of the 1% manual tally for the contest(s). By statutory definition, risk-limiting audits must take account of all types of ballots.


Somewhat different transparency requirements apply to the 1% manual tally and any risk-limiting audits.

The statute provides that the manual tally “shall be a public process,” and that public notice of the time and location of both the audit and the selection of the audit sample be given. Cal. Elec. Code, div. 5 § 336.5; § 15360(e). The manual audit report is to be included in the certification report, which is filed with the Secretary of State. However, the audit report is not required to be published.

Under statute, the regulations for any risk-limiting audits must ensure that the audit process is observable and verifiable by the public, including disclosing the methods used to select samples and to calculate the risk, providing public opportunity to verify that the correct ballots were inspected during the audit, and providing public opportunity to observe the voters’ marks on the ballots during the audit. The regulations as of September 2020 can be found here.

Audit Counting Method

Both the 1% manual tally and any risk-limiting audit are conducted manually.

Type Of Audit Units

California’s 1% manual tally is conducted upon precincts; mail ballots may be audited separately from in-person ballots. Risk-limiting audits sample individual ballots.

Contests & Issues Audited

The 1% manual tally covers all contests that appear on the ballot; if a contest is not represented in the original sample, county officials must select an additional precinct in which to audit that contest.

Effective August 2020, county election officials could conduct a risk-limiting audit for one or more contests fully contained within the county in lieu of the 1% manual tally for the contest(s). Cal. Elec. Code, div. 15 § 15367. The secretary of state is tasked with creating regulations to establish procedures and requirements including disclosing the methods used to select samples and to calculate the risk. Assembly Bill 2125 and Cal. Elec. Code, div. 15, § 15360.

Addressing Discrepancies

There is no provision for expanding the 1% manual tally. Risk-limiting audits of specific contests expand until the risk limit is met for each contest or a full hand count results.


The audit must be conducted “during the canvass” and a report of the audit must be included in the “certification of the official canvass.” However, any risk-limiting audit will follow certification, twenty-eight (28) days after election day in California.

Binding On Official Outcomes

The 1% manual tally statute specifies that the voter-verified paper audit trail shall govern if there is a discrepancy between it and the electronic record — but this is very unlikely to affect the outcome. See Cal. Elec. Code, div. 15, § 15360. (Risk-limiting audits of specific contests can lead to full hand counts that are binding on the outcomes.)

Oversight & Conduct

As the chief elections official, the Secretary of State has oversight over the entire elections process, including election audits. The random selection of the precincts to be audited is conducted in each individual county, and the audits are conducted by local election officials.

Ballot Protection

The elections official shall maintain and document an uninterrupted chain of custody for each ballot card and each ballot storage container. Chain of custody logs shall be available for public inspection after the canvas. These procedures will be published on the elections official’s website at least 5 days in advance of the audit. For more information, see Cal. Elec. Code, div 14 § 14405 and div. 15 § 15367.

Additional Targeted Samples

Additional precincts for the manual tally may be selected at the discretion of the elections official.

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