Eyewitnesses instructed to close their eyes during retrieval recall more correct and fewer incorrect visual and auditory details. This study tested whether eye closure causes these effects through a reduction in environmental distraction. Sixty participants watched a staged event before verbally answering questions about it in the presence of auditory distraction or in a quiet control condition. Participants were instructed to close or not close their eyes during recall. Auditory distraction did not affect correct recall, but it increased erroneous recall of visual and auditory details. Instructed eye closure reduced this effect equally for both modalities. The findings support the view that eye closure removes the general resource load of monitoring the environment rather than reducing competition for modality-specific resources. (Contains 2 figures and 1 footnote.)