Answer

STAR Voting incentivises expressive voting, not bullet voting

STAR Voting has not demonstrated high or problematic levels of bullet voting. Across the thousands of elections and polls held with STAR, the trend is that the vast majority of voters do vote expressively, scoring multiple candidates. As you would expect, voters who have multiple candidates on their side are more likely to score multiple candidates than voters who actually only have one candidate they support.

The STAR Voting runoff specifically encourages voters to be expressive and to show their honest preference order to ensure that no matter who the finalists are, their vote will go to the finalists they prefer. 

In the current system there's little to no incentive to learn about candidates beyond your favorite, but with the 5 star ballot, voters have a strong incentive to learn about the candidates so they can show their preferences and level of support. Doing so helps you get better representation.

This is especially true for minority voters - those whose true favorite is unlikely to win. With the current system if your candidate doesn't win, your vote doesn't make a difference. With STAR Voting even if your favorite can't win, your vote still helps prevent your worst case scenario. If the STAR runoff comes down to your 1 star candidate versus your 0 star candidate, your full weight goes to preventing your worst case scenario from winning. 

In real elections, STAR Voting has not demonstrated high or problematic levels of bullet voting. Across the thousands of elections and polls held with STAR, the trend is that the vast majority of voters do vote expressively, scoring multiple candidates. As you would expect with preference voting in general, voters who have multiple candidates on their side are more likely to score multiple candidates than voters who actually only do have one candidate they support.

 

Bullet voting can be honest voting in some cases:

The fact is, some voters only like one candidate. For these people a 'bullet vote' is an honest vote. The key is to ensure that voters who do have a more nuanced opinion are empowered and encouraged to vote more expressively, and STAR Voting does this.

In some elections there may be one faction that runs only one candidate while other faction(s) run multiple candidates. These lopsided elections are the most vulnerable to vote-splitting and spoilers, and STAR Voting does a great job of preventing spoiled elections even under these kinds of stress tests by allowing voters to support all the candidates they prefer.

The Independent Party of Oregon 2020 primary election, which used STAR for the first time, was one such example. Close to 1/2 the voters leaned Republican (based on their 1st choice votes) and in all three races there was only one Republican candidate, whereas there were multiple left candidates in all three races. As expected, many Republican voters gave 5 to the Republican and 0s to the others. On the left, which ran more candidates, most voters were much more expressive, showing which Democrat or Progressive they preferred and who else they supported. In all three of these elections the STAR winner was both the Condorcet winner (preferred over all others) and the highest scoring candidate, so there is no doubt that even in these types of difficult scenarios, STAR Voting was able to elect the correct winners and avoid spoiled elections. 

 

How does STAR Voting compare to Ranked Choice Voting in regard to bullet voting?

Both STAR Voting and Ranked Choice Voting (RCV) do a good job of encouraging voters to be expressive and in both systems bullet voting is not a viable or effective strategy. This is because both STAR and RCV are preference voting methods with an instant runoff. In this sense they have a lot in common. 

In this FairVote* article they cite the fact that the average/median amount of bullet voting in RCV elections is 32%As the FairVote article shows, bullet voting trends have much more to do with the distribution of candidates than with the voting method itself.

In RCV there have been many elections that have had higher rates of bullet voting than we saw in the Independent Party of Oregon primary, which is why it's important to have a larger, statistically relevant sample size and take context into consideration before we draw broader conclusions.

 

What about the Later No Harm criterion? 

Some people are concerned that because STAR Voting doesn't pass Later No Harm that voters wouldn't have any incentive to score candidates beyond their favorite. That's simply not true. Again, the STAR Voting runoff specifically encourages voters to show their honest preference order, at least between all relevant candidates, to ensure that no matter who the finalists are, their vote will go to the finalists they prefer. STAR Voting also strongly incentivises voters to give their honest favorite a full 5 stars. 

In election science there are a number of desirable criteria that voting methods can either pass or fail. Some of them, like the "Favorite Betrayal" criterion and the "Later No Harm" criterion are mutually exclusive and it's been proven that it's impossible for any voting method to pass all desirable criteria 100% of the time. In voting reform, competing priorities need to be balanced. 

While it's impossible to pass both 100%, it's absolutely possible to excel at both in practice. STAR Voting easily gets an A on both criteria, which has been clearly demonstrated in the peer reviewed literature.

 

Further Reading:

Q: Does STAR Voting fail the Later No Harm criterion?

Learn more about Favorite Betrayal, Later No Harm and the Spoiler Effect in this ground breaking article

Read the peer review on metrics for comparing voting methods, voting method accuracy, and strategic incentives

* Veteran readers of this site may be surprised to see us citing FairVote as a source on bullet voting rates. While they still have a long way to go before the electoral science community considers them to be credible, this article is a step in the right direction.

 

Q: Is STAR Voting committed to open sourced implementation? Q: How does STAR Voting help marginalized communities? Q: What's wrong with our current system? Q: Is this the same as Ranked Choice Voting? Q: Why bother with the automatic runoff? Shouldn’t we just elect the candidate with the highest score? Q: What if I give both finalists the same score? Q: Would STAR Voting cost money or save money? Q: What if voter behavior isn't ideal under STAR Voting? Q: Is STAR Voting vulnerable to strategic voting? Q: Why is it a 0 through 5 star rating? Not more or less? Q: Does STAR Voting pass One-Person-One-Vote? Q: Is STAR Voting constitutional? Q: Has STAR Voting been used for elections before? Q: Can we use STAR Voting for Presidential elections? Q: Can STAR Voting elect winners who are not majority preferred? Q: Are STAR Voting elections secure? Q: Does the League of Women Voters Support or Oppose STAR Voting? Q: Why is a blank counted as a zero? Q: Are STAR Voting ballots "summable," or do they require centralized tabulation? Q: Why doesn't RCV break two-party domination? Q: Wasted Votes?: What's the difference between an exhausted ballot in RCV and an equal preference vote in STAR? Q: Will voters bullet vote with STAR Voting? Q: How are ties in STAR Voting broken? Q: What is a preference matrix? Q: Does STAR Voting fail the Later No Harm criterion? Q: Wouldn't I want to "bury" a strong second choice and give a higher score to a weaker opponent to help my favorite win? Q: Is STAR Voting compatible with Electoral Fusion (aka Fusion Voting)? Q: Did the Independent Party and Democratic Party of Oregon abandon STAR Voting?