expression
alleging diminution
A legal expression used in the context of claiming that a record is incomplete or deficient. Rare outside legal or formal documentary settings.
裁判で、弁護側は記録欠缺の主張を行った。
In the trial, the defense made an allegation of diminution of the record.
A compound of 記録 (record), 欠缺 (deficiency, gap), and 主張 (claim, assertion). The term is a technical legal phrase.