Via Slashdot we come across SCOTUSScores.com, a site which purports to give a clear visual representation of the Supreme Court’s voting patterns over the years. Each justice is given a color coding for every term representing how he voted.

There’s just one problem with it: It’s biased.

Updated below the fold…

No, really? A biased chart of the Supreme Court just in time for a fight over Obama’s nominee to the court, and probably future nominations to come? Who’d have thought it? But take a look: The colors are skewed. The left and right are set to different scales, where the deepest red color shows up at about 5, for Clarence Thomas, while the deepest blue color only shows up when you get to about 6.5, for William O. Douglas. See the problem?

By cursory inspection, all left-leaning justices will look more ‘moderate’ and ‘centrist’ than the right-leaning justices. William Rehnquist’s “Lone Ranger” period is exaggerated, while Thurgood Marshall is moderated.

This cannot stand, so I have fixed the chart:

Sure, the chart’s not as colorful, but now it’s true to the data and that’s what counts.

Update: I got an email from Alex Lundry at TargetPoint. With his permission, it follows:

Neil,

I tried posting a comment to your RedState blog, but it won’t let me, as I’ve only just signed up for an account.

First, thanks for posting the link to SCOTUSscores.com and for the feedback. It’s especially great to see people interacting with the visualization and repurposing it. Well done.

Your point about the coloring is a legitimate criticism, and in fact, we plan on adding an absolute color reference in our next update. But perhaps some more details about precisely how the coloring works could clear up any lingering confusion about the existing display options.

There are actually four different ways to display color on the chart. The colors are chosen based upon the Min, Max, and Median of the area we are comparing. So, in the first view, the “overall” view, the darkest Red is anchored to the maximum ideology number across all justices and all terms, the darkest Blue is anchored to the minimum score, and the purest white is anchored to the actual median number.

The second “compare” option, “within each seat, row” calculates separate color anchors for each row.

Similarly, the third compare option, “within each year, column” calculates separate color anchors for each column.

I hope this helps you better understand the colors and the decisions we made on the chart. I would argue that the views in our chart and in your version are each, in their own way, “true” to the data.

Let me know if you have any other questions.

- Alex

p.s. As far as the lying and bias accusations go, you might want to check out my bio and TargetPoint’s work/client list and see precisely what is we do. We are most certainly NOT liberal apologists.

My reply: Yes, we do have a 24 hour waiting period before posting is allowed. We get that many troublemakers that it’s essential.

But as for TargetPoint, I do have to retreat from some of my claims. They have a track record of working for the right, most notably Bush/Cheney 2004. I’m now inclined to believe that this wasn’t malicious, but rather was just an unfortunate choice of a right-leaning group to give some fodder to the left on the eve of a big battle.

So no, I don’t think they’re lying. I just think their defaults are wrong. I thank Alex and hope TargetPoint keeps working on that chart to improve it.