Let me give you two headlines, and you can tell me your reaction to each:
A) Big Oil Finances the Republican Party
B) Congressional Votes Correlated with Big Oil Contributions
From the headlines you’d think the articles are about two separate facts about the world. That is, that the two facts are independent. One can read the first article and then still be surprised after reading through the second article. A friend of mine says about the second hypothetical headline, “I think the votes are sort of taking it to the next step of association.” Compare those with these headlines:
A) Factory Emissions Tied to Deadly Cancer
B) Life Expectancy Lower in Factory Towns
Here you’d say the articles are about the same thing: clearly, because more deadly cancer means more deaths, and that means lower life expectancy. If everyone already knew (A) from an expose last year, when a newspaper reports (B) we say what an idiot the reporter must have been — he just reported the same thing again.
That’s what’s happening with money-and-votes analyses. The facts are more complicated, and the results are less clear, so it’s easy to overlook the problem here. But the problem is here.
We all already know that Big Oil gives more to Republicans than to Democrats. If you didn’t know, you know now. It’s an interesting point; no qualms there. Since the Republicans support big business and the Democrats support the environment (whatever, you get the idea), it makes sense. Fine.
But because of that, I know immediately that any vote related to Big Oil is likely to go down with an uneven distribution of money coming from Big Oil between Yes votes and No votes. In fact, it has nothing at all to do with Republicans and Democrats having different views on oil in particular. It’s just that Republicans and Democrats either all vote together (on naming post offices) or vote against each other (on everything else). The votes where everyone agrees are not relevant here: you can’t have an uneven distribution of money between Yes and No votes when there aren’t No votes to begin with. Since the relevant votes are almost always split on party lines, of course there is going to be a correlation between money and votes.
What I mean by of course is that no one should be surprised to learn about a big correlation between money and votes if it has already been established that there is a correlation with contributions to a particular party. Finding out the magnitude, in dollars, of the correlation doesn’t change anything. It might as well be reported as “Big Oil Gives $XXX more to Republicans than to Democrats.” This headline is less exciting, but it’s the same thing. Throwing in votes just makes it sound more important, and it is misleading because it makes it sound like there is something new and nonobvious to be learned.
Let’s look at what is being reported. I paraphrase from Follow the Oil Money (sorry guys):
Of the 25 Representatives who took the most Big Oil money per term between 2000 and 2007 Representatives, 23 were Republicans. Of the 25 Representatives who took the least amount of Big Oil money per term between 2000 and 2007, 22 were Democrats. … Representatives who voted against clean energy proposals took more than 4.5 times more oil money than those who voted in the public interest.
Why not just say “Republicans” took more than 4.5 times more oil money than “Democrats”? (Well, the number may change a bit of course, but that’s the idea.) The votes have nothing to do with it unless it is showed that the votes were something other than decided roughly on party lines. It’s another question entirely whether the money influenced the votes, or whether votes influence future contributions — a question that is unsolved.
I raised a similar issue previously with some numbers from MAPLight. To paraphrase their analysis and interjecting my own totals:
Opponents of H.R. 1424 gave an average of $22,479 to Republicans and $12,646 to Democrats. These industry groups gave an average of $22,693 to legislators who voted No on this bill, compared to $14,183 to legislators who voted Yes.
Can you guess what happened? It’s no accident that $22,479 is close to $22,693 and $12,646 is close to $14,183. The Republicans predominantly voted No and the Democrats predominantly voted Yes. Actually the vote wasn’t exactly evenly split, which makes the results more interesting. You can still see an effect of money on the vote beyond the party difference, as I noted in that post, but it’s a much smaller correlation.