Intoxicated Tales

Much research has been conducted to determine the reliability and validity of an eyewitness testimony of a crime. There is a high level of importance put on the word of one or more individuals who claim to have seen a crime, life as the believed criminal sees it could be at stake. So what can be said regarding the validity of an eyewitness that is under the influence of alcohol at the time of the crime? Alistair Harvey, Wendy Kneller and Alison Campbell want to know just that. The researchers wanted to find out if intoxication played any positive or negative role in the eyewitness' memory and face identification. A total of 120 students participated in the study (78 females, 42 males). The breath alcohol content (BrAC) of each participant was tested before beginning the research to ensure all levels started at zero. The participants were randomly assigned to two groups (alcohol or no-alcohol groups). Participants in the alcohol group were given enough of an alcoholic beverage to put most of the students at a 0.08% blood alcohol concentration (BAC). The non-alcohol group was given pure orange juice in the same quantity as the alcohol group received alcohol. They were also made aware that the drink was non-alcoholic. All drinks were consumed within 10 minutes and participants were made to spend 20 minutes sitting to allow for absorption. To ensure no alcohol compounds were left behind for further absorption, all participants rinsed their mouths after the 30 minutes. Participants were made to watch slides that depicted a scenario while their eye movement was being measured. The next day students returned to the lab, had to pass a sobriety test to ensure valid results and continued to answer 16 true/false questions relevant to the slides seen the day before. The study found that the correct identification of the group that received alcohol was equally as accurate as the sober group. Implications that could come from this study include the change that could occur in the court systems to prove a suspect innocent/guilty.

These changes could also cause re-trials for some inmates already convicted if an intoxicated eyewitness was questioned but found to be unreliable due to intoxication. This would cost time and money for the court system. There is also a limitation that can easily be seen in this study; the fact that tolerance to alcohol was not taken into consideration. After developing a tolerance to alcohol, it is possible for motor skills, mental comprehension, etc. to improve with the tolerance. If a participant was severely tolerant of alcohol it could skew the results.
Abstract

Harvey, A.J., Kneller, W., Campbell, A.C. (2013). The elusive effects of alcohol intoxication on visual attention and eyewitness memory. Applied cognitive psychology. 27, 617-624.