noun
identification parade; police lineup; witness identification
Colloquial term used in criminal investigations for the procedure where witnesses identify a suspect from a group of people or photographs.
被害者は面割りで犯人を特定した。
The victim identified the perpetrator in a lineup.
警察は面割りを行うために数人の容疑者を集めた。
The police gathered several suspects to conduct an identification parade.
Compound of 面 (めん, 'face') and 割り (わり, 'assigning' or 'splitting'), literally 'face assignment'. The exact historical derivation is uncertain, but it likely originated in police jargon.