Partisanship and Racial Bias in Signature Matching: Explaining the Ballot Rejection Gap in California

Author: Michael Herndon

In Partisanship and Racial Bias in Signature Matching: Explaining the Ballot Rejection Gap in California, Michael Herndon showcases his research findings on the ballot rejection gap in California. In the current vote-by-mail (VBM) process, millions of people’s identities are verified/adjudicated by comparing copies of their signature as a measure of fraud-prevention. This process happens on a massive scale each election and has been described as “witchcraft” and “ripe for error,” in part because of the significant variance in people’s signatures due to factors such as age, health, mood, pen quality, or the use of non-Roman characters (e.g., Chinese characters). Furthermore, the individuals tasked with verifying signatures are granted substantial discretion, often making subjective, case-by-case judgments while under pressure and with limited oversight and formal training. As a result, despite there being no evidence of widespread signature fraud on mail ballots, California has rejected more than 200,000 ballots for signature problems since 2020 and the vast majority of these rejections are estimated to be legitimate voters who are disproportionately young and nonwhite.

Michael Herndon is a senior research fellow at the UCLA Voting Rights Project who specializes in research regarding vote-by-mail ballot rejection, having published peer-reviewed scholarship and expert reports on the rejection patterns, and briefed the Latino, Black, and Asian state legislative caucuses on ballot rejection data in California. Mr. Herndon and Senior Data Scientist Michael Rios recently published a research paper related to this issue entitled, “Bureaucratic Bias or Voter-Side Factors? Testing Competing Explanations for Racial Gaps in Vote-By-Mail Ballot Signature Rejection.”