Matthew Longo, Daphna Canetti and Nancy Hite-Rubin have a forthcoming article in the American Journal of Political Science (ungated version) looking at the consequences of Israeli checkpoints for Palestinian attitudes toward Israel and political violence. They take advantage of an external political decision to “ease” border controls between Israel and the West Bank, comparing attitudes over time among local Palestinians near a checkpoint that was eliminated and near a very similar checkpoint that remained in place. Their objective was to replicate as closely as possible the conditions of an experiment in which one randomly allocates individuals to a “treatment” group (those who are affected by the easing of the local checkpoint) and a “control” group (those who remain affected by the checkpoint). This would allow them to make a good case that any changes in attitudes among Palestinians who lived near the former checkpoint were caused by the checkpoint’s disappearance.

As it turns out, the conditions for an experiment weren’t perfectly replicated. Attitudes changed among the control group (Palestinians located near the checkpoint that stayed), as well as among the treatment group (Palestinians located near the checkpoint that’s gone). However, the changes went in opposite directions. Palestinians who don’t have to go through the checkpoint any more “were significantly less likely to support violence against Israel, or the militant Islamic group, Hamas.” Palestinians who still had to go through a checkpoint became significantly more likely to support violence.

This suggests that checkpoints increase tendencies to support violent action, rather than reduce them. Further evidence from the data strongly suggests that checkpoints make Palestinians more likely to support violence because of the extended humiliation they involve.

Even some quarters of the Israeli military admit that humiliation at checkpoints is excessive, and perhaps counterproductive. For example, Judge Advocate General of the Israeli Defense Forces (IDF) Menachem Finkelstein, admitted that “there were many – 28 too many – complaints that soldiers manning checkpoints abuse and humiliate Palestinians and that the large number of complaints ‘lit a red light’ for him” (Ha’aretz 2003). He was speaking from a strategic vantage, concerned with the potential danger this might cause Israelis down the road.

Israel-Palestine issues tend to arouse controversy and bitter disagreement (as witnessed, for example, by comment threads to newspaper articles discussing related issues). This makes data-driven research especially valuable.