In today's Arizona redistricting case, the least persuasive arguments focus solely on the good of independent redistricting commissions and the evils of gerrymandering. That, of course, was the thrust of Arizona's ballot initiative that was enacted, and some briefs in this litigation are treating the Supreme Court as a kind of ratifying commission for this political decision.

But here's one question I like to float to students and others skeptical of gerrymandering. (Disclosure: this blog is named after a quotation from Elbridge Gerry.) Are competitive elections always a good thing?

There are at least two immediate costs that come with a competitive election: increased price tag on elections, and increased uncertainty in outcomes leading to recounts and litigation.

Arizona, case in point.

Even though Arizona has just nine members in the 435-member House of Representatives, it boasted two of the four most expensive races in outside spending (or, depending on your politics, "dark money") in 2014. Competitive elections often mean that the price of running an election increases--and that the amount of outside spending increases.

One House race was decided by just 167 votes, certified after a recount--because more competitive elections are closer, and those often trigger recounts and possible litigation.

It might be that, on the whole, voters, as a policy matter, as Arizonans did, prefer competitive elections. But it shouldn't be seen as a costless decision.