In a normal situation, the drunk fan at the bar might have realized that the person walking behind him did not intentionally fall into him. In a crowded bar, people get jostled. But after a few drinks, this power of reasoning seems to evaporate.

This issue was explored in a paper in the October 2010 issue of and Social Psychology Bulletin by Laurent Begue, Brad Bushman, Peter Giancola, Baptiste Subra, and Evelyn Rosset.

The authors had men participate in a study in which they evaluated some drinks and also performed some other judgments. Half of the men were told that the drinks were going to have in them, and the other half were told that they would not. Half of each of these groups was assigned to have a drink that actually had alcohol in it while the other had a drink with no alcohol. This design allows the researchers to separate the effects of believing you are going to drink from the effects of actually being drunk.

The men who drank alcohol were given enough to drink to get their blood alcohol level to about 0.10%, which is the level at which many states use to say that someone is driving drunk.

The results of this study suggest that both your beliefs about whether you are going to drink and your consumption of alcohol affect your judgments of blame. People who thought they were going to drink judged the same proportion of the sentences as being intentional whether they drank alcohol or not. However, people who did not think they were going to drink were far more likely to say that an action was intentional rather than accidental when they had alcohol than when they did not.

This result suggests that both alcohol and beliefs about drinking make you more likely to blame others for their actions rather than recognizing the effects of the situation on people's actions.

Before thinking a bit about what this result might mean, I do want to express one frustration with this research paper. The overall pattern of data is pretty clear that the effect of alcohol on blame depends on whether you think you are going to drink. However, when the statistical analysis was done, the overall difference between those who drank and those who did not achieved the level of statistical reliability normally used for these kinds of studies. The statistical interaction between alcohol and beliefs about whether you are going to drink missed that level of reliability by .02. The authors treated this result as if the beliefs about drinking had no effect on judgments. That is unfortunate.

Ok, why do these results matter?

One effect of alcohol is that it can reduce your ability to control your actions. You might never get into a fistfight with someone under normal circumstances, but still end up hitting them if you have had too much to drink. If you combine that tendency with an increased tendency to want to blame someone for their actions just by being in in which alcohol is present, then you can see why parties with alcohol can get out of control. This tendency may also make couples more likely to fight if they have been drinking, because they may be more prone to view actions taken by their partner as intentional.

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