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Cooperation: substantial assistance motions

Helping the government investigate or prosecute someone else is the most powerful way to reduce a federal sentence. It depends entirely on a government motion: the defendant cannot ask for it alone.

Guidelines Manual effective November 1, 2025Updated October 4, 2026

General information about how the guidelines work, written by web developers, not lawyers. It is not legal advice about any case; see the disclaimer.

How it works

  • §5K1.1 motion: on the government's motion stating that the defendant provided substantial assistance, the court may sentence below the guideline range.
  • 18 U.S.C. §3553(e) motion: allows a sentence below a statutory mandatory minimum.
  • Rule 35(b): a similar reduction after sentencing, for help given later.

The court decides how large a reduction to give, considering the significance and usefulness of the help, its truthfulness and completeness, its nature and extent, any danger or injury to the defendant or family, and its timeliness (§5K1.1(a)).

Cooperation is not the safety valve

The safety valve requires only telling the government everything about one's own offense, and the judge decides whether it applies. Substantial assistance requires help against others, and only the government can file the motion. A calculator cannot predict a cooperation reduction, which is why this tool shows the range before any such motion.

Frequently asked questions

How much time does cooperating take off a federal sentence?

There is no fixed amount. The court decides, based on the factors in §5K1.1(a). Reductions vary widely by case and district.

Can a judge reduce a sentence for cooperation without a government motion?

Not under §5K1.1 or §3553(e); both require the government's motion. A judge can still consider cooperation among the §3553(a) factors when choosing a sentence within or outside the range.

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