Punch Card Technology and the Racial Gap in Residual ... - CiteSeerX

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Punch Card Technology and the Racial Gap in Residual Votes Justin Buchler, Matthew Jarvis, and John E. McNulty Votomatic-style punch card voting systems produce higher rates of residual voting than other technologies, but the effect of punch card voting systems is not uniform. Minority voters are less likely to have their votes properly recorded with punch card systems than are nonminorities. This racial gap occurs, for the most part, because punch card systems lead to higher rates of “undervoting” by minorities. When election administrators switch to other systems, such as optical scan systems, the racial gap is significantly reduced. Punch card voting systems, then, constitute a disproportionate obstacle to minority voting. This effectively gives less weight to votes cast by minorities than to votes cast by nonminorities, and arguably violates constitutional requirements for equal voting rights. The mechanism is similar to the literacy tests that were abandoned after the 1970 amendments to the Voting Rights Act.

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unch card voting has been with us for over forty years. It originated at the University of California, Berkeley, where Professor Joseph Harris and his collaborators came up with a method of using simple, inexpensive, easily portable equipment to record votes that could be tabulated mechanically using the computer technology of the day. Because punch card systems were cheap and their results could be tallied quickly, the technology was widely adopted. In the 2000 presidential election, almost one third of all voters (32.1 percent) used punch cards—more than any other type of voting technology. The majority of the punch cards used in the United States are Votomatic-style. Similar to computer cards, they record votes, and are prescored with columns of small, perforated rectangles known as chads. The names of the candidates do not appear on these cards.1 The dramatic events in Florida in the aftermath of the 2000 presidential election highlighted a problem with Votomaticstyle punch card technology that election professionals had known about for some time: the likelihood of a vote not being counted is much higher with Votomatic-style punch cards than it is with any other type of voting technology.2 If votes lost due to the use of Votomatic-style punch cards were random, then

Justin Buchler is visiting assistant professor at Oberlin College ([email protected]). Matthew Jarvis is a PhD candidate at the University of California, Berkeley (mjarvis@socrates. berkeley.edu). John McNulty is a PhD candidate at the University of California, Berkeley ([email protected]). The authors are grateful to UC Berkeley’s Survey Research Center for research support and are deeply indebted to Henry E. Brady. Our thanks also to the anonymous reviewers and to the editorial staff at Perspectives on Politics for their helpful suggestions and hard work on our behalf.

the problem would be largely benign. Unfortunately, empirical research shows that this is not the case. The process by which Votomatic-style punch cards cause “residual votes” is not random.3 Most notably, members of minority groups (especially African Americans) have much higher rates of residual voting—and, consequently, invalidated votes 4 —when using punch cards than nonminorities. Some research has noted that Votomatic-style punch card systems are the worst offenders for disproportionate invalidation of minority votes.5 The result is a system that gives greater weight to votes cast by nonminorities, through a mechanism very similar to literacy tests. Thus there is both a clear problem and a simple remedy—switch to a technology that does not incur this discrepancy.6 This paper reviews evidence of the racial bias in vote invalidation introduced by Votomatic-style punch card systems. We then place these findings in the context of case law on voting rights to argue that Votomatic-style punch card systems may violate constitutional requirements and the Voting Rights Act.

Data Analysis The problems with Votomatic-style punch cards in general have been well documented. Additionally, there is a wellestablished racial gap in residual votes—minority voters have their votes invalidated at higher rates than white voters. Some research has also noted that this gap is partly affected by voting systems, and that Votomatic-style punch card systems are the worst offenders for disproportionately invalidating minority votes. The following analysis presents simple data to demonstrate these findings. We rely on simple bivariate models without controls such as education or wealth because, from the perspective of “fairness,” it does not matter why punch card systems lead to a racial gap in vote invalidation. What matters is that there is a gap, and that the gap can be virtually eliminated by switching September 2004 | Vol. 2/No. 3 517

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U.S. Elections rates in non–punch card counties, but the important point is that punch cards are significantly worse than all other systems. Some of the high residual vote rate in punch card counties can be explained by demographics since residents of many of them have lower average levels of education, and such counties typically have higher residual vote rates anyway. However, punch card counties tend to have higher residual vote rates than we would expect even after controlling for education. Minority voters in the United States therefore face two threats to the valid counting of their ballots. First, they tend to be less educated and less wealthy than white voters, which means that they are likely to have higher residual vote rates. Even controlling for these factors, though, minorities are still more likely than similarly situated whites to cast invalidated ballots.10 Second, the rate at which minorities’ ballots are invalidated by punch cards is higher than it is for any other type of voting technology. Thus, the basic problem faced by minority voters is compounded by punch card voting systems.

Figure 1 Presidential residual vote in 2000 by machine type and percent minority in the county

to newer technologies. For obvious reasons, we do not have individual level data on whose votes were invalidated, so we are forced to examine the relationship between county or precinct-level residual vote rates and aggregate demographic figures. We also chose not to use statistical methods such as King’s ecological inference model. While there are limits to the ability of his model to address these issues, the primary reason for our choice of techniques is that our objective is to keep the models as simple as possible. In addition, there are many homogenous units (all minority or nonminority) for the tract and precinct-level data that we present, so that inferences can be made without undue concern about the ecological fallacy. Our findings are remarkably consistent regardless of the method we use, and every study done so far has come to the same substantive conclusions. We are simply presenting results that have previously been established using more complex methods in order to give context to the legal debate. Punch cards and residual vote rates Our first analysis is based on county-level data on voting systems used in 2000 and residual vote rates in the 2000 presidential election. These data come from a thorough auditing of a data set purchased from Election Data Services.7 In figure 1 we see a dramatic demonstration of the racial gap in vote invalidation. Figure 1 plots the residual vote for each county against the percent minority, with a separate line for punch card and non– punch card counties.8 Note that punch card counties have higher residual vote rates for all racial compositions, and that the slope of the line is greater for them. In other words, the vote invalidation gap between minorities and nonminorities is higher when a county uses punch card voting systems.9 There is, of course, a great deal of variation between residual vote 518

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The impact of system upgrades The problem of vote invalidation is largely a problem of the Votomatic-style punch card voting system, and it is significantly reduced (if not almost eliminated) when counties switch from that system. To demonstrate this point, consider figure 2. Using data from Fresno County, California, figure 2 plots each census tract’s residual vote rate in 1996 and 2000 along with the percent of each tract that is minority. We use Fresno County because it is an example of a county that switched from Votomatic-style punch cards between the elections of 1996 and 2000 11 to a newer, precinct-scanned optical scan system (the Diebold Accuvote ES-2000).12 The advantage of this approach over the cross-sectional analysis presented previously is that here we can compare how the same political unit behaves using different types of systems. Comparing 1996 to 2000 shows that optical scan systems are vastly superior to Votomatic-style punch cards, both in terms of the total number of residual votes and in the racial gap of the system. Figure 2 demonstrates that, when Fresno switched systems, every single tract had smaller residual vote rates, regardless of racial composition. Note also that the racial gap all but disappeared with the optical scan system. Nearly homogenous white and minority precincts are almost equal in terms of residual voting rates. Votes are now being counted, and they are being counted in an essentially unbiased fashion.

nonparametric regression fit for a plot of residual vote rate versus percent minority in each census tract in the nine California counties (Alameda, Los Angeles, Mendocino, Sacramento, San Bernardino, San Diego, Santa Clara, Shasta, and Solano) that used Votomaticstyle systems in both 1996 and 2000.13 Although there was some improvement in 2000, the two lines are very similar. Figure 3b shows that even though the three counties that did change systems looked like all the other Votomatic-style counties in 1996, they looked completely different in 2000, with a much flatter regression line and a much smaller intercept. By switching systems, these counties had much lower residual vote rates for all groups, and Fresno is just one of three counties in California that dramatically lower rates for minorities. switched from Votomatic-style punch card systems between The adoption of optical scan systems by counties that for1996 and 2000. Marin County changed to the same system merly used Votomatic-style punch card systems led to a that Fresno did, and San Francisco County went from a Votodecreased rate of residual voting for nearly every census tract, matic to an Optech Eagle system (another precinct-count regardless of racial composition. Furthermore, note that the optical scan system). Figures 3a and 3b demonstrate that ‘racial gap’ (indicated by the slopes of the lines) has decreased Fresno’s improvement was not unique. Figure 3a displays a dramatically. While the analysis was based only on California (because we have particularly good data on that state), the Figure 3a results are consistent regardless Presidential residual vote in 1996 and 2000 for tracts in California counties using of the units being studied. Votomatic style in both elections

Figure 2 Residual vote in 1996 and 2000 by percent minorities in census tract in Fresno

Undervotes vs. Overvotes: The Source of the Problem Why do Votomatic-style punch card voting systems invalidate minority votes at a higher rate than nonminority votes? Ballots without a valid vote come in two forms, overvotes and undervotes. Which of these occurs more frequently with minorities, and which type varies by system? Unfortunately, national data are not available on undervotes and overvotes, but we can look at some cases where they are available. Previous research has shown that undervotes are the main September 2004 | Vol. 2/No. 3 519

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separately by precinct. We categorize precincts by the percent of the population that is minority. We compute the average overvote rate, and we plot those averages in figure 4 by category for the 1996 and 2000 elections. Note that no consistent patterns emerge. However, figure 5 shows the same comparisons with respect to undervotes. In 1996, when Votomaticstyle punch cards were being used, the more minorities there were in a precinct, the higher the undervote rate. In 2000, when the optical scan system was used, there was no consistent relationship between the percent of a precinct that was minority and the undervote rate. Not only was there a dramatic improvement in the undervoting rate for all voters, minority voters in the 2000 election were source of variation in residual voting rates.14 To demonstrate no more likely than white voters to undervote. The same patthat point, we use precinct-level data from Madison County, tern of discrepancies in undervoting rates with VotomaticIllinois, from the 1996 and 2000 elections. We do this for two style punch card systems appears in other counties we have reasons: The county switched from a Votomatic punch card examined as well. Unfortunately, undervoting is not comsystem to a precinct-scanned optical scan system (the Election monly reported as a separate statistic by counties, but this is Systems and Software Optical Scan M100) between 1996 and the pattern we have seen consistently in counties from Florida 2000; and it recorded the number of overvotes and undervotes to Illinois to California. The problem is typically resolved when counties change systems away from Votomatic-style punch cards. Figure 4 We cannot eliminate the posPresidential overvotes by percent minority in Madison County, Illinois precincts sibility that minority voters in the counties we examined were more inclined to vote in the 2000 presidential election than in the 1996 election; nor can we rule out the possibility that minority voters who lived in punch card districts in 2000 had less desire to vote in the presidential election than those who lived in any other districts. However, each of these hypotheses is unlikely, and it is preposterous to assume that both are true. Minority voters do not have their votes recorded at the same rates as white voters. Much of this gap is due to the counting problems of Votomaticstyle punch card systems. Figure 3b Presidential residual votes in 1996 and 2000 for tracts in California counties changing from Votomatic style systems

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Figure 5 Presidential undervotes by percent minority in Madison County, Illinois precincts

Disproportionate weighting of votes Another way to look at this issue is to compute voting “weights”: estimates of the ratio of the number of voters of type A (minorities) that are required to cast as many valid votes as one voter of type B (nonminorities). We can do this by simply referring back to figure 2. Recall that figure 2 plotted residual vote rates in Fresno, California, census tracts when they used a Votomaticstyle punch card system, and when they used an optical scan system. Since Fresno has a large number of nearly homogeneous census tracts, we can use predicted residual vote rates from that graph for 0 percent minority tracts as an estimate of the percent chance that a white person’s vote will be invalidated. Similarly, we can use the predicted residual vote rate for a 100 percent minority tract as an estimate of the percent chance that a minority’s vote will be invalidated. Again, since we have a large number of nearly homogeneous tracts, the problems associated with ecological inference here are minor. Table 1 presents these predicted probabilities of vote

Table 1 Predicted residual vote rates in hypothetical census tracts* County makeup Voting system

0% Minority

100% Minority

Ratio

Votomatic-style punch card Optical scan

2.5% 0.5%

5% 1%

1.026 1.005

*Based on data from Fresno County, California.

invalidation with a Votomaticstyle punch card system and with an optical scan system. Based on census tract–level data from Fresno, a 0 percent minority tract using a Votomaticstyle punch card system will have approximately a 2.5 percent residual vote. A 100 percent minority tract using the same system will have approximately a 5 percent residual vote. If we take these percentages as estimates of the percent of votes, by race, that are invalidated, we can divide the percent of white votes that are successfully counted by the percent of minority votes that are successfully counted. This will generate a ratio indicating how much more likely a nonminority vote is to be counted than a minority vote. Doing so produces a ratio of 1.026 for a Votomaticstyle punch card system, and a ratio of 1.005 for an optical scan system. These are, of course, rough figures. The point estimates, therefore, should be viewed with some skepticism, although the substantive results—that minority votes are invalidated more frequently than nonminority votes with Votomatic-style punch card systems—are extremely robust. When the probabilities of two votes being counted differ, that is neither mathematically nor substantively different from giving one vote greater weight than another. In Votomaticstyle punch card counties, it takes 1026 minority voters to generate the same number of valid votes as it does 1000 white voters; with systems other than punch card, this ratio drops to 1005:1000. Put another way (taking reciprocals), minority voters are only 97.5 percent as effective with punch cards as white voters, whereas they are 99.5 percent as effective as white voters when using an optical scan system.

Legal Implications A strong case can be made that due to unequal patterns of vote invalidation, Votomatic-style punch card voting systems violate the one person, one vote principle established in Gray v. Sanders (1963). The importance of that principle has been most prominently addressed in the case law on redistricting. The Supreme Court has acknowledged for decades the importance of giving votes equal weight. Writing for the majority in Reynolds v. Sims (1964), for example, Chief Justice Earl Warren argued that “[I]t is inconceivable that a state law to the effect that, in counting votes for legislators, the votes of citizens in one part of the state would be multiplied by two, five or ten, while the votes of persons in another area would be counted only at face value, could be constitutionally sustainable.” September 2004 | Vol. 2/No. 3 521

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Giving one person’s vote twice as much weight as another person’s is not constitutionally permissible. Why then would it be constitutionally permissible to count one person’s vote with 1.026 times the weight of another person’s? Votomatic-style punch card voting systems, as we demonstrated earlier, do just that. Thus, if we know that a particular voting system discounts a vote with a greater probability than another system, and that as a result, one group’s votes are counted more frequently than another, how is that different from the type of unequal weighting that Chief Justice Warren condemned? Furthermore, isn’t such weighting made worse given the history of voting policies that discriminate against minorities? While the chief justice’s statement (and the decision in Reynolds) referred to redistricting plans that placed voters in districts with vastly different populations, the rationale of his argument—as well as those found in similar decisions such as Baker v. Carr (1962) and Wesberry v. Sanders (1964)—can just as easily be applied to the issue at hand. While giving one vote 1.026 times the weight of another may be acceptable in some cases, the Supreme Court has rejected redistricting plans for less: in Karcher v. Daggett (1983) it rejected a New Jersey plan because the largest district had 0.6984 percent more people than the smallest district. Still, a higher standard must be placed on voting technologies. After all, one may sensibly debate whether districts should have equal population with respect to people, citizens, voting-age citizens, eligible voters, et cetera, in order to ensure equal weighting. But even if such a standard were logically clear, given that lines are drawn based on census data taken every ten years, equal population across districts is impossible to sustain. In fact, equal population is not the only legitimate concern with respect to redistricting, and the courts do allow some deviation from perfect population equality. Sometimes, those deviations may even provide an advantage to minorities, in contrast to the findings about voting systems. If we know, however, that a voting system leads to a racial gap in the counting of votes, and that the system in question is out-performed by all other systems with respect to every other measure (except, perhaps, cost), there is no constitutionally permissible reason to accept any gap above that which is unavoidable. As the data have shown, changing technology does not eliminate the gap entirely. Yet, if a simple upgrade in voting technology can reduce that gap, and there are no other, more compelling reasons not to change technologies (and what can be more compelling than basic electoral fairness?), there can be no constitutional defense of the system in question. The analogy just made to equal weighting of votes in redistricting may seem a bit odd in connection with voting technologies. A more obvious comparison is to the history of literacy tests as criteria for voting. Successfully voting on a Votomaticstyle punch card system is clearly possible, but apparently more difficult under certain circumstances. For example, the notorious “butterfly ballot” (a punch card design) used in Palm Beach County, Florida during the 2000 presidential election required voters to notice that the second hole did not line up with the second name on the left-hand side of the ballot.15 More generally, Votomatic systems require voters to success522

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fully line up the correct holes on a nameless ballot with the correct names on the device into which the ballot is inserted. While neither task may seem particularly difficult, there is a strong correlation between aggregate educational attainment and the percent of ballots discounted.16 Thus the racial gap in education may explain much of the racial gap in discounted ballots. Such a challenge to the successful exercise of the franchise is indistinguishable from a literacy test for voting. Thus it is important to look at the legal history of literacy tests. Literacy tests were most notoriously used by southern states after the passage of the 15th Amendment in order to ensure that African Americans could not vote. However, in Lassiter v. Northampton County Board of Elections (1959), the Supreme Court held that literacy tests were constitutionally permissible because they were, on their face, neutral with respect to race. Furthermore, the Court argued that, since political decisions are complex, there was a compelling interest in limiting suffrage to those who can read. Yet, with the inclusion of language implying that discriminatorily applied literacy tests would not be permitted, that decision left the door open for future challenges. In Davis v. Schnell (1949), the Court held that a test that gave too much discretion to the registrar was being used for discrimination. Congress responded to this history in 1965 by including in §4(a) of the Voting Rights Act (VRA) a suspension of all literacy tests for five years in states with a history of discriminatory voting practices. The ban was a limited one, implying an acceptance of the idea that literacy tests under some circumstances are permissible, which is consistent with the logic of Lassiter. However, 1970 amendments to the VRA expanded the ban to cover the entire nation, and the Court unanimously upheld that ban in Oregon v. Mitchell (1970). In that case, the state of Oregon claimed that since it had a history of administering the test fairly, the test was constitutionally permissible, and the ban overstepped congressional authority. The Court disagreed, and argued that due to a history of unequal educational opportunities, literacy tests were inherently racially unfair. Since the ban on literacy tests in discriminating states dramatically improved the equality of voting, why not let it work across the country? By 1970, literacy tests were essentially rejected from the American system. Votomatic-style punch card voting systems, which share the character of the effect (though not the magnitude), do not seem substantively different. Additionally, consider the issue of discriminatory intent and discriminatory effect, particularly in light of Oregon v. Mitchell. For the purposes of racial vote dilution, the Court held in City of Mobile v. Bolden (1980) that discriminatory purpose must be shown in order for a policy (in that case, at large elections rather than single-member districts) to be considered a violation of the Voting Rights Act (VRA). However, in the 1982 reauthorization of the VRA, Congress circumvented that interpretation by adding language to §2 indicating that discriminatory effects would be considered violations, even absent intent.17 Votomatic-style punch card voting systems were certainly never intended to systematically disenfranchise minorities, but

they nevertheless appear to have that effect. Furthermore, while late-night comedians may make jokes about whether or not we should let people vote if they cannot figure out how to use a Votomatic system, such a requirement is substantively indistinguishable from the literacy tests that have been rejected for their discriminatory effects. Whether the problem results from a racial gap in education, poor election administration, or any other phenomenon we have yet to explore is, by law, irrelevant. What is relevant is that minority votes are systematically discounted more frequently than white votes when Votomaticstyle punch card systems are used, and that the gap is reduced dramatically when the voting system is changed.

Recent Developments Since this article was originally written, these arguments have been indirectly tested by the courts. In Common Cause, et al. v. Jones (2002), a collection of groups representing minority voters sued the state of California on the grounds that Votomaticstyle punch card systems disadvantaged minority voters for many of the same reasons discussed earlier. As part of the settlement, the state decertified these systems, and agreed to have them eliminated by the next election after the settlement was made, which would have been the March 2004 primary. However, a successful petition drive mandated an election to recall Governor Gray Davis in October 2003. Many counties were unable to update their voting systems by the date of the recall. As a result a coalition led by the Southwest Voter Registration Education Project filed a lawsuit to postpone the recall until the March 2004 primary. Thus, the courts were asked to either permit an election using decertified voting systems, or violate the legal requirement to have the recall held between 60 and 80 days of the petition’s certification. In Southwest Voter Registration et al. v. Shelley (2003), a threejudge panel of the Ninth Circuit Court of Appeals ordered a postponement of the recall on the grounds we have suggested. However, that decision was overturned by an en banc (full bench) panel of the Circuit Court. While the en banc decision ruled that the recall could be held with punch card systems, the decision was based on the relative importance of a timely recall versus a well-administered one. The Circuit Court ruled that while Votomatic-style punch card systems were flawed and could potentially cause problems, the uncertainty of those problems made them subordinate to the concern of a timely recall. In fact, the recall passed overwhelmingly, and Arnold Schwarzenegger easily won the vote to replace Davis, so the election was not close enough for the decertified systems to have affected the outcome. However, even under these circumstances, the courts acknowledged that there was a legitimate claim against these voting systems under the Fourteenth Amendment and the VRA.

Summary This paper has presented some new evidence that Votomaticstyle punch card technology induces a racial bias in vote invalidation. This evidence adds to the already considerable amount presented elsewhere on this same phenomenon. The racial bias

in vote invalidation with Votomatic-style punch card systems is particularly distressing in the context of the history of discrimination against minorities’ voting rights. Given the case history of vote weighting and literacy tests, constitutional law may even mandate that these systems be replaced with some other technology in any political unit with a significant minority population. The evidence accumulated here and elsewhere combined with the clarity of case law on disenfranchisement lead to the clear conclusion that Votomatic-style punch card systems must be replaced.

Notes 1 Voters insert this card into a slot in the voting machine and use a stylus device to punch out chads on the cards to indicate their selections. Datavote machines are another kind of punch card system. They use a staplerlike tool to create holes in ballots. Unlike Votomatic machines, Datavote machines have the names of candidates appear on the medium where the punches are made. 2 On the general problems with Votomatic-style punch cards see Brady et al. 2001; Caltech-MIT Voting Technology Project 2001. 3 The “residual vote” in an area is the difference between the total number of people who show up to the polls to vote and the total number of valid votes cast in a given election. Residual votes can be undervotes or overvotes. Undervotes occur when a voter does not make a sufficient mark for any candidate (e.g., a dimpled chad). Overvotes occur when a voter makes marks indicating a vote for multiple candidates in the same race (e.g., marking both Gore’s name and Buchanan’s name on a butterfly ballot). While both types of errors may be intentional, if a system causes unintentional residual votes, it is invalidating votes. 4 Brady et al. 2001; Hansen 2000; Herron and Sekhon 2003; General Accounting Office 2001; House Committee on Government Reform 2001; Knack and Kropf 2001; Tomz and Van Houweling 2003. 5 Knack and Kropf 2001; Tomz and Van Houweling 2003. 6 This discrepancy does not commonly occur with any other type of voting technology, though there are indications that similar problems exist with some centralcount optical scan systems. 7 Brady et al. 2001 includes a detailed description of the data set and the auditing process we used. 8 In this case, punch cards include Datavote systems as well as Votomatic-style systems because of data limitations. We fit ordinary least squares (OLS) lines to the data for simplicity. Punch card counties behave noticeably different (and worse) than counties using any other counting technology. We restrict our analysis to the simple dichotomy of punch card/non-punch card to keep the presentation focused on the much larger problem presented by punch cards than by the smaller differences between the other types of systems (optical scan, lever, paper ballots and direct recording electronic devices). September 2004 | Vol. 2/No. 3 523

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The variance between punch cards and all other types of systems is larger than the variance within these other types. Brady et al. 2001; Knack and Kropf 2001; Tomz and Van Houweling 2003. We consider this fact to be largely proven and accepted, although we do note that some county election officials are still skeptical (personal interviews). In presenting the data here, we simply wish to reiterate this point, potentially for a new audience, and draw more normative conclusions from this evidence. Brady et al. 2001. Unfortunately, we do not believe that a comparison of all counties in the United States that switched voting technology between 1996 and 2000 is feasible. We have investigated the available data on voting technologies in use in 1996 and found it to be severely lacking. Indeed, the data presented here were subjected to a painstaking review process that required two independent sources of confirmation of voting technology in use for every county in the United States. In collecting these data, we found that information about what systems counties used was woefully inaccurate, and, in many cases, seemingly impossible to determine (for instance, some counties supposedly changed to a lever system in 2000, even though vendors had stopped selling such systems by then). We are only willing to compare system switches when we are certain that they occurred, as we are in the cases presented here and some others. For more on the problem of older data, see Brady et al. 2001. Optical scan systems have two main variations. Centrally scanned optical systems collect ballots from each precinct and scan them all together at a central location. Precinct scanned systems scan each ballot at the polling place, which allows election workers to notify people of problems on their ballots, and to give voters a chance to correct them. Our analysis is based on California because we trust our data on that state from 1996. Obtaining reliable data on old elections becomes increasingly difficult as time passes because obtainable data sets have frequent errors, and it is more difficult to audit older data because of poor record-keeping. However, our California data from 1996 are more reliable than 1996 data from most other states, although we have no reason to believe that patterns are any different in other states. Brady et al. 2001. Brady 2000. Brady et al. 2001. In doing so, Congress attempted to force the Court back into the type of reasoning applied in White v. Regester (1973), which invalidated a multimember district plan on the grounds that it had the effect of reducing the voting power of African Americans. Brady et al. 2001; Knack and Kropf 2001; Tomz and Van Houweling 2003.

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References Baker v. Carr. 369 U.S. 186 (1962). Brady, Henry E. 2000. What happened in Palm Beach County? http://socrates.berkeley.edu/;ucdtpums/palm2.pdf. Brady, Henry E., Justin Buchler, Matt Jarvis, and John McNulty. 2001. Counting all the votes: The performance of voting technology in the United States. Berkeley: University of California. http://ucdata.berkeley.edu/new_web/ countingallthevotes.pdf. Caltech-MIT Voting Technology Project. 2001. Voting: What is, what could be. Pasadena and Cambridge: California Institute of Technology and MIT. http://www.vote. caltech.edu/Reports/july01/July01_VTP_%20Voting_ Report_Entire.pdf. City of Mobile v. Bolden. 446 U.S. 55 (1980). Common Cause, et al. v. Jones. No. 01-03470, C.D. Cal. 2002. Davis v. Schnell. 81 F. Supp. 872 (MD Ala. 1949). General Accounting Office. 2001. Statistical analysis of factors that affected uncounted votes in the 2000 presidential election. Washington, DC. http://www.gao.gov/ new.items/d02122.pdf. Gray v. Sanders. 372 U.S. 368 (1963). Hansen, Bruce E. 2000. A precinct-level demographic analysis of double-punching in the Palm Beach presidential vote. Working Paper. November 20. University of Wisconsin. http://www.ssc.wisc.edu/;bhansen/vote/florida2.pdf. Herron, Michael C., and Jasjeet S. Sekhon. 2003. Overvoting and representation: An examination of overvoted presidential ballots in Broward and Miami-Dade Counties. Electoral Studies 22 (1): 21–47. House Committee on Government Reform. 2001. Income and racial disparities in the undercount in the 2000 presidential election. Washington, DC. http://www.house.gov/ reform/min/pdfs/pdf_inves/pdf_elec_nat_study.pdf. Karcher v. Daggett. 462 US 725 (1983). Knack, Stephen, and Martha Kropf. 2001. Invalidated ballots in the 1996 presidential election: A cross-level analysis. Working Paper. University of Maryland and University of Missouri, Kansas City. Lassiter v. Northampton Election Board. 360 U.S. 45 (1959). Oregon v. Mitchell. 400 U.S. 112 (1970). Reynolds v. Sims. 377 U.S. 533 (1964). Shaw v. Reno. 509 U.S. 630 (1993). Southwest Voter Registration Education Project v. Shelley. D.C. No. CV-03-05715-SVW (2003) Tomz, Michael, and Robert P. van Houweling. 2003. How does voting equipment affect the racial gap in voided ballots? American Journal of Political Science 47 (1): 46–60. Wesberry v. Sanders. 376 U.S. 1 (1964). White v. Regester. 412 U.S. 755 (1973).