How have U.S. federal and state audits assessed the security of voting machines used in key 2020 swing states?
Executive summary
Federal and state post‑election audits and reviews of voting machines in 2020 largely found that machines produced accurate tallies where standard, nonpartisan procedures were followed, while partisan or ad hoc “forensic” reviews often failed to meet professional audit standards and in some cases introduced security problems of their own [1] [2] [3]. State and federal election‑security bodies have repeatedly concluded there is no evidence voting systems were compromised to change votes in 2020, even as audit processes exposed administrative weaknesses and uneven recordkeeping in several jurisdictions [4] [5].
1. What typical audits looked like and what they were meant to test
Routine post‑election tabulation audits in 2020 compared samples of paper ballots to electronic tabulations to check machine accuracy and to provide public confidence; these state‑run audits were written and implemented according to preestablished procedures and, when done by election professionals, were intended to detect counting errors rather than to probe invented conspiracy theories about hacking [3] [5] [6].
2. Wisconsin: nonpartisan review affirmed machine accuracy while flagging administration issues
A nonpartisan Legislative Audit Bureau review in Wisconsin examined statutory pre‑election machine tests and samples of absentee certificates and found that voting machines correctly tabulated ballots in nearly all tested cases and did not reveal widespread fraud, while also making dozens of recommendations to improve administrative consistency such as better clerk testing windows and voter‑registration maintenance [2] [1] [7].
3. Arizona and Maricopa: hand tallies, partisan scrutiny, and mixed perceptions
Maricopa County’s recounts and hand tallies — including a hand count overseen by county officials and later a controversial partisan review — ended up reaffirming that Joe Biden received more votes than Donald Trump in the county, and accredited auditors reported no evidence of widespread fraud, even as partisan reviews (notably those conducted by outside groups) attracted significant national attention and criticism for lacking standard audit controls [8] [3].
4. Georgia: exhaustive recounts and risk‑limiting audit efforts exposed logistical and data questions
Georgia conducted multiple machine recounts, a statewide hand tally, and a risk‑limiting audit that involved external vendors; research examining Fulton County has raised concerns about missing or inconsistent machine records in some precincts and argues that gaps in chain‑of‑custody and ballot manifests can limit what recounts and audits can guarantee — a critique that frames some audits as potentially “security theater” if underlying inventories are incomplete [5] [9].
5. Pennsylvania: nonstandard audits prompted official decertification over access breaches
An audit arranged in a rural Pennsylvania county that allowed a third party access to election systems prompted the state’s acting secretary of state to decertify that county’s voting equipment, with officials saying the certified system had been compromised by providing unauthorized access to databases and equipment — illustrating how improvised forensic approaches can themselves create security vulnerabilities [10].
6. State boards, federal agencies, and watchdogs: consensus on no evidence of machine tampering, plus caution about ad hoc probes
State election boards and federal cybersecurity officials repeatedly concluded the 2020 election was secure and that there is no evidence voting systems were altered to change votes; they have cautioned against random public inspections of machines as risky and urged adherence to established post‑election audit protocols, while outside watchdogs like the Brennan Center warned that partisan reviews frequently fail to meet standards of objectivity and basic reliability [4] [5] [3].
7. The larger picture: audits validated machine counts but revealed administrative gaps and political fault lines
Across swing states, professionally conducted post‑election audits and certified recounts overwhelmingly confirmed machine tabulations where paper records existed, but audits also spotlighted inconsistent procedures, recordkeeping lapses, and the danger that partisan or poorly designed “forensic” reviews can undermine both security and public confidence — a split between technical findings of machine accuracy and persistent political distrust that audits alone cannot resolve [1] [2] [3].