The official line is that the “no” vote won the referendum in Colombia. The internationally lauded peace treaty with the FARC guerillas was rejected . . .
But did “no” actually win?
The numbers divide four ways, rather than just two “no” and “yes” answers: 6,431,376 against the treaty, 6,377,482 in favour, 86,243 unmarked ballots, and 170,946 nullified ballots.
The referendum process itself was without doubt transparent and fair . . . But there were nonetheless several inevitable sources of statistical error in the counting process that could have swamped the razor-thin victory margin of 53,894.
Spagat and Johnson first point out errors in ballot counting:
As a large research literature has made clear, we can reasonably assume that even well-rested people would have made mistakes with between 0.5% and 1% of the ballots. On this estimate, about 65,000-130,000 votes would have been unintentionally misclassified. It means the number of innocent counting errors could easily be substantially larger than the 53,894 yes-no difference.
But this would only make a difference if the miscounts were biased, not if the mistakes were happening at random.
Spagat and Johnson then write:
Second, there were 170,946 nullified votes. As the photo below shows, the ballots were so simple that it’s hard to imagine how there could be so many invalid ones.
Of course, it is correct to toss out any ballot with both “yes” and “no” marked, but it seems surprising that so many ballots were apparently spoiled this badly. Again, the consistency of the counters’ decisions could have been decisive.
Then there are the blank or nullified ballots. It’s quite possible that many of the 86,243 unmarked ballots were simply marked very lightly, meaning their votes did not register in the tired eyes of well-meaning volunteer counters – and the nearly 270,000 voters whose ballots were rejected as blank or null must have had some voting intention that they somehow failed to express.
So these ballots represent 270,000 voting failures, more than four times the victory margin. Even if many of these ballots were reasonably well-classified, this figure is an enormous red flag.
What about biases? Spagat and Johnson write:
We know of no evidence of cheating, and Colombia is to be lauded for the seriousness of its referendum process, but the distinction between intentional and unintentional misclassification by individual counters can occasionally become blurred in practice.
As a study that asked voters to judge “ambiguous” ballots demonstrated, those doing the counting can be driven by unconscious biases. . . .
In total, therefore, the result presents as many as 400,000 opportunities for classification mistakes. That’s before counting any systematic human behaviours not listed above. This represents a numerical uncertainty that swamps the victory margin of 53,894.
None of the above analysis proves that most voters on Sunday supported the peace treaty, but there’s an immense difference between declaring that “no” won and declaring the result inconclusive. This referendum has momentous implications, not just for the Colombian people but also for the many national governments and the United Nations that supported the peace deal. It is very sad that a country’s future may be dictated by an inaccurate declaration (one readily amplified by international media).
Interesting. I don’t know anything about Colombia myself, so all I can say is there’s a lot to think about here.