Interstate Voter Registration Crosscheck Program

Map of the states that have not publicly withdrawn from the Interstate Voter Registration Crosscheck Program.

Interstate Voter Registration Crosscheck (commonly referred to as IVRC or Crosscheck) is a database software program designed which aggregates voter registration records from multiple states to identify voters who may have registered or voted in two or more states. Crosscheck was developed in 2005 by Kansas Secretary of State Ron Thornburgh in conjunction with Iowa, Missouri, and Nebraska. The program is currently under fire for its inaccuracy, poor data security, and potential for racial bias. To date eight states have withdrawn from Crosscheck citing the inaccurate data and risk of violating voters' privacy rights. Crosscheck is accused of facilitating unlawful purges of voters in a racially discriminatory manner. Secretary of State Kris Kobach is currently being sued for violating the constitutional right to privacy for careless handling of voter data in Crosscheck.

Origins, Stated Purpose, and Expansion

Crosscheck was initiated in December 2005 at the Midwest Election Officials Conference (MEOC) by the office of the Kansas Secretary of State in coordination with Iowa, Missouri and Nebraska. The program combines each state's voter rolls into a database and seeks to identify potential duplicate registrations by comparing first name, last name, and full date of birth. In 2006, the first crosscheck was conducted using voter registration records from Kansas, Iowa, Missouri, and Nebraska.

The program is administered by the office of the Kansas Secretary of State as a free service to all member states.

Under Secretary Kris Kobach, the program expanded rapidly from thirteen states in 2010 to a peak of 29 states in 2014. In 2017, Crosscheck analyzed 98 million voter registration records from 28 states and returned 7.2 million "potential duplicate registrant" records to member states.

Inaccurate Results

Crosscheck considers two voter registrations potential duplicates if they match on first name, last name, and full date of birth even if the last four digits of the social security number (SSN4) of the two records do not match, or when one or both SSN4 are missing.

Matching based on first name, last name, and date of birth "fails for practically all common American names" according to ID Analytics analysis of a database of over 300 million unique records.

Crosscheck's use of loose matching standards leads to a high rate false positives: pairs of voter registration records lacking a match on SSN4 but who are identified as "potential duplicate registrants" by Crosscheck. Although false positives create a myriad of issues, the Kansas Secretary of State's office does not publicly release the percentage of their widely publicized "potential duplicate registrants" which are false positives. Independent researchers point to public data from Virginia's 2013 Annual Report on List Maintenance which documents a 75% false positive rate.

For voters and member states, misidentification can be costly. Each voter misidentified faces incremental privacy risk when their personally identifying information is sent to at least one state beyond his or her state of residence, and risks being inactivated or removed from voter rolls. In Ada County, Idaho, election officials relied on Crosscheck's list of "potential duplicate registrants" to mistakenly remove 765 voters. None were duplicate registrants.

To avoid inappropriate deletion of eligible voters as occurred in Ada County, member states must invest in extensive processing to vet each Crosscheck record. In May of 2018, the New Hampshire Secretary of State's office reported that 817 work hours over nearly a year were required to process the 2017 Crosscheck results for their state. Despite that intensive effort, they found no evidence of widespread double voting. Similarly, Virginia's 2015 Annual List Maintenance Report states "the Crosscheck program does not have a direct fee associated with it, however, the initial data received from Crosscheck requires significant agency handling to determine what data is usable and what data is not usable. Crosscheck data is prone to false positives since the initial matching is only conducted using first name, last name, and date of birth. The need to greatly refine and analyze Crosscheck data has required significant ELECT staff resources that are not accounted for when proponents claim the program is "free." "

To date, eight states (Alaska, Florida, Kentucky, Massachusetts, New York, Oregon, Pennsylvania, and Washington) have withdrawn from the free program. The Illinois legislature passed a bill forcing the state's withdrawal from Crosscheck but it was vetoed by Governor Rauner.

Despite over seven million "potential double registrants" being "flagged" by the Crosscheck program in 2014, less than four people were charged with voting more than once, and not a single flagging led to a conviction, casting doubt on the system's usefulness.

Discrimination Controversy

The loose matching standards used to identify "potential duplicate registrants" by the Kansas Secretary of State also raise significant concerns about the opportunity for racial bias in list maintenance. According to "Health of State Democracies", "50 percent of Communities of Color share a common surname, while only 30 percent of white people do," so that in the program's flagged lists, "white voters are underrepresented by 8 percent, African Americans are overrepresented by 45 percent; Hispanic voters are overrepresented by 24 percent; and Asian voters are overrepresented by 31 percent".

After examining "potential duplicate registrant" lists from some of the participating states, investigative reporter Greg Palast claimed the Crosscheck system "disproportionately threatens solid Democratic constituencies: young, black, Hispanic and Asian-American voters" with the intention of securing Republican victories. Palast concluded this was achieved by eliminating discrete individuals based on nothing more than similarity of name, a method with a "built-in racial bias" that especially eliminated voters from targeted minorities with a more limited pool of given names, for example, Hispanic voters named Jose Garcia.

However, presence on the "potential duplicate registrant" list does not mean a voter was removed from the rolls.

Data Security and Data Handling Lapses

Articles in ProPublica and Gizmodo, relying on information provided by activists in Illinois and Kansas, revealed in fall 2017 that the Kansas-managed database holding nearly 100 million records of private voter data were protected by security protocols so flawed they could be "hacked by a novice". Kansas Secretary of State Kris Kobach demurred saying "I don't concede there is a problem" but also pledged to quickly fix the data security issues. After a subsequent consultation with the Division of Homeland Security, Kobach quietly halted Crosscheck for 2018 in advance of his gubernatorial race in Kansas. His successor as Kansas Secretary of State Scott Schwab, has stated without supporting evidence that he believes Crosscheck is "pretty darn good" and plans to re-start it once in office.

In June 2018, the ACLU of Kansas filed a class action lawsuit against Kansas Secretary of State Kris Kobach alleging that their constitutional right to privacy was violated by his office's careless handling of a Crosscheck file.

Limits to Crosscheck's Utility

Crosscheck is frequently cited, without supporting evidence, as a critical tool to prevent voter fraud. Critics note that Crosscheck's utility is limited to a very specific type of fraud (double voting), in a very specific situation (across state lines), at very specific times (general elections only). Double voting within a state cannot be detected. Double voting in a primary cannot be detected. Voting on the records of a deceased person cannot be detected.

In addition to being plagued by false positives and limited scope, Crosscheck also suffers from false negatives: the failure to recognize voters who are registered in two states if there is even a slight variation in their name. For example, Vic Miller registered in Kansas would not be recognized as the same as Victor Miller registered in Missouri despite the same full date of birth and last four digits of social security number.

Do Voter Registration Maintenance Programs Do More Harm than Good?

Debate about Crosscheck is part of a larger, ongoing controversy over whether or not such voter registration programs are a valid means of protecting against fraud.

A landmark study by researchers at Stanford, University of Pennsylvania, Yale, and Harvard quantified the tradeoff between voter accessibility and electoral integrity when purging a likely duplicate registration from another state using Crosscheck. Their analysis of Crosscheck results in from Iowa in 2012 and 2014 suggests that for every double vote prevented, use of Crosscheck's proposed purge strategy impedes approximately 300 legitimate registrations. Note that this finding is in a "best practices" scenario in which all false positives have been removed.

The authors emphasize that election authorities should consider the tradeoff between election access for all eligible voters and fraud prevention.