Background of Bias: Subtle changes in line up backgrounds increase the own race bias

In police photo lineups there can sometimes be small variations in shades and hues of the background images due to the faces being filmed under different lighting and cameras. Own race bias refers to a situation where people are better at remembering the faces of those who are the same race as them and find it more difficult to recognise faces from a different race. In this paper we investigated the influence of small colour variations in backgrounds for the recognition of Black and White faces. Across 3 experiments we found when small changes were introduced into the backgrounds of the images this increased false identifications for previously unseen Black faces, but not White faces. This finding suggests that the police need to ensure that the backgrounds of the photo lineups they use are all uniform to reduce mistaken identifications of innocent suspects.  

A dataset collected through Gorilla for face recognition data for Experiments 2 and 3 from the paper have been uploaded in Excel. The data consists of percentage of responses from the face recognition tasks, see the Excel doc for data labels.

Please cite Havard et al (2023) A Background of Bias: Subtle changes in line up backgrounds increase the own race bias, Journal of Police and Criminal Psychology, in press, if using this data.

在警务照片排列中，由于拍摄时不同照明和摄像机的影响，背景图像的色调和色彩有时会出现细微的差异。种族偏见现象是指个体在记忆与自己种族相同的人的面孔时更为得心应手，而识别不同种族的面孔则显得更为困难。本研究深入探讨了背景色彩微小的变化对于黑白人种面孔识别的影响。通过三项实验，我们发现当图像背景中引入微小变化时，这会加剧对之前未见过的黑人面孔的错误识别，而对白人面孔则没有这种影响。这一发现表明，警方需要确保他们使用的照片排列背景均保持一致，以减少对无辜嫌疑人的误认。通过 Gorilla 平台收集的用于实验2和3的人脸识别数据集已上传至Excel。数据包括人脸识别任务中各响应百分比的统计数据，具体数据标签请参阅Excel文档。若使用此数据，请引用 Havard 等人（2023）的论文《背景偏见：排列背景中的微妙变化加剧了种族偏见》，发表于《警察与犯罪心理学杂志》，待刊。