Last November, I discussed AZ’s rejection of a top two primary and made the following comment about California’s new primary system:
My guess is that you’re not going to see much moderation as a result of this system.
Well that guess is apparently correct. The folks over at Monkey Cage did with California what I had not done with Louisiana, i.e., look at the ideology of the candidates in connection with the election outcomes. They found that the top two primary did not have a moderating influence on candidates. The primary issue seemed to be that voters did not distinguish between centrists candidates and more extreme candidates, often rating them the same on an ideological scale. In other cases, voters did not try to locate the centrists, instead relying on their own partisanship to make their decision.
Perhaps open primaries could work in correlation with other reforms, as well as an educated electorate; however, they do not provide greater moderation on their own.
See also: Security Blanket Primaries