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Comment by koolba | Hacker News Reader

Is there a particular standard used to determine that a given map is considered gerrymandered? Or is it like porn, i.e., you know it when you see it?

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    > Is there a particular standard...?

Well in this case, the legislator literally admitted to gerrymandering. See the opinion:

    Rather than seeking to advance any democratic or 
    constitutional interest, the state legislator
    responsible for drawing the 2016 Plan said 
    he drew the map to advantage Republican
    candidates because he “think[s] electing
    Republicans is better than electing Democrats.”
    Ex. 1016, at 34:21–23. But that is not a
    choice the Constitution allows legislative
    mapdrawers to make.

I don't think there's an easy way prove gerrymandering. The only antidote is to require serious (and audit-able) bipartisan cooperation when re-drawing districts.

That's the million dollar question, and it's likely to be the end point of the SCOTUS discussion on the matter.

https://fivethirtyeight.com/features/gerrymandering-is-on-tr...

> In a 2004 opinion, [Justice Anthony Kennedy] expressed alarm at the practice of extreme partisan gerrymandering but said the court should hold off on outlawing it. He also left the door open to ruling differently in the future, as long as lawyers provided a suitable way to measure when gerrymandering goes too far. He said that without that measurement, the court runs the risk of becoming too involved in a decision-making process that is legally mandated to state legislatures.

Nothing official, but people are working on quantifying it. https://www.washingtonpost.com/graphics/2017/politics/courts... Even if it's not perfect, it's useful to point out the most egregious cases.

As you might imagine, it is possible to consider this as a purely mathematical problem and to thereby come up with measures of gerrymandered-ness. It is a widely studied field. e.g.:

https://digital.lib.washington.edu/researchworks/bitstream/h...

https://www.researchgate.net/profile/Matthew_Dube/publicatio...

The reason it's so fascinating though, is that because it is a many-variable optimization problem where 1) many of the variables conflict and 2) we haven't actually agreed on the desired optimum. In the end it still very much has a "you know it when you see it" quality, and nobody has come up with math that definitively says "yes this is" or "no this isn't".

Actually, it's maybe a little like spam filtering.

it would be relatively trivial to simulate a null distribution -- generate 10^n quasi-random maps which then give you the null distribution of voters across districts. Compare that null distribution with an actual map and if it sits beyond the x-th percentile you can call it 'gerrymandered'.

The typical standard is "are Democrats disadvantaged by this?" If so, gerrymandering.

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