Wade v. United States
Holding or rule used
In the § 3553(e)/USSG § 5K1.1 posture actually decided, a prosecutor's substantial-assistance filing decision is reviewable for unconstitutional motive or lack of rational relation to a legitimate government end, but assistance allegations alone do not require relief, discovery, or a hearing.
Material limitation
Use only for the bounded proposition stated here. The exact Rule 35 or 36 posture, circuit law, record, agreement, modification vehicle, appealed order, preservation, and requested relief remain separate where identified.
Official source and pinpoints
504 U.S. 181 (1992), 504 U.S. 185–86: https://www.govinfo.gov/content/pkg/USREPORTS-504/pdf/USREPORTS-504-181.pdf