So while some voters may decide on a given proposition as, say, the 12th contest on the ballot, residents of other precincts may not choose to approve or reject the same proposition until they first have voted on, for example, a total of 21 contests. Since the number of local contests presumably is unrelated to how voters in a precinct feel about a certain proposition, Augenblick and Nicholson were able to analyze this as a so-called natural experiment.

They found that when a certain state proposition appeared later on the ballot, voters were more likely to vote no (or to abstain from voting altogether). “When we get tired of choosing, we are more likely to want to preserve the status quo, which for state and local propositions means voting no,” says Augenblick. He and Nicholson estimate that the proportion of no votes on the propositions that they studied would have been, on average, 3.2 percentage points lower if the propositions had appeared at the top of the ballots instead of their actual positions. They reckon that this would have been enough to swing the outcome of 24 contests (or 6 percent of all contests), which means that they would have been approved rather than rejected. In other words, decision fatigue is a blessing for the “no” campaigns.

Even though the study only looks at contests in San Diego, it seems reasonable to assume that voters elsewhere in America also are affected by the sheer number of contests that appear on the ballot. The results extend beyond state and local propositions, too: The authors reckon that a late position on the ballot significantly increases the number of votes for the first-listed candidate in a race, as people are more likely to want to make an easy and quick selection.

So there is a cost to multiplying the number of decisions that are presented to voters. The benefit of holding many electoral contests is that people can get more involved in public policy and have a say on their representatives and on issues that could have a large impact on their lives. But the downside is that voters may end up making poor choices that they would not have made if their minds were fresher. Unfortunately, there is no simple solution to the problem. In some countries, such as Canada, national and local elections are spread out across multiple days, which make individual ballots shorter. But more elections may increase costs and can also lower turnout. Another option is to encourage absentee ballots to give voters more time to digest each choice they have to make. In Oregon, for example, all elections are conducted by mail. However, if people wait to fill out the ballots until right before they submit them, this may not result in any more careful deliberation than walking over to a traditional polling place.

Unfortunately, leaving the system unchanged may encourage the groups that introduce ballot initiatives to try to get their proposals as high up on the ballot as possible. Indeed, during the 2012 election season in California, supporters of a tax-increase proposition were accused of convincing the state legislature to pass a bill that put their proposal at the top of the propositions on the ballot. One way to resolve this would be to randomly determine the order in which contests of a certain type—such as local propositions—appear on the ballot. This could at least potentially help eliminate the incentive for powerful groups to game the system in order to place their propositions at the top.