United States Court of Appeals
                            FOR THE EIGHTH CIRCUIT
                                     ___________

                                     No. 06-2532
                                     ___________

United States of America,                 *
                                          *
             Appellant,                   *
                                          * Appeal from the United States
      v.                                  * District Court for the
                                          * Northern District of Iowa.
Amanda Williams,                          *
                                          *
             Appellee.                    *
                                     ___________

                               Submitted: December 13, 2006
                                  Filed: January 29, 2007
                                   ___________

Before BYE, COLLOTON, and BENTON, Circuit Judges.
                           ___________

COLLOTON, Circuit Judge.

       The Sentencing Reform Act provides that a district court has “limited authority
to impose a sentence below a statutory minimum,” upon motion of the government,
“so as to reflect a defendant’s substantial assistance in the investigation or prosecution
of another person who has committed an offense.” 18 U.S.C. § 3553(e). This case
presents the question whether a district court, after reducing a sentence based on
substantial assistance pursuant to § 3553(e), may reduce the sentence further based on
factors, other than assistance, set forth in 18 U.S.C. § 3553(a). We hold that it may
not. Where a court has authority to sentence below a statutory minimum only by
virtue of a government motion under § 3553(e), the reduction below the statutory
minimum must be based exclusively on assistance-related considerations.

       Amanda Williams pled guilty to conspiracy to distribute more than 500 grams
of methamphetamine within 1000 feet of a protected location. At sentencing, the
government filed motions under USSG § 5K1.1 and 18 U.S.C. § 3553(e) to reduce her
sentence based on the provision of substantial assistance to authorities in the
investigation or prosecution of other persons. A motion under § 5K1.1 authorizes the
sentencing court to depart below the applicable advisory guideline range in
determining the advisory guideline sentence, and a § 3553(e) motion permits the court
to sentence below a statutory minimum. See Melendez v. United States, 

,
128-29 (1996).

       Prior to any reduction for assistance, the advisory guideline sentence for
Williams was 120-121 months’ imprisonment, and the applicable statutory minimum
was 120 months. The district court granted the substantial-assistance motions and
announced that it would reduce the term of imprisonment to 78 months based on
Williams’s assistance. The court then invoked § 3553(a) to reduce the sentence
further, to a final term of 60 months’ imprisonment, based on Williams’s young age,
medical history, drug use, and limited criminal history. The government does not
challenge the district court’s reduction of the sentence to 78 months based on
substantial assistance, but argues that the additional reduction to 60 months was
legally impermissible, because the court relied on factors other than substantial
assistance. This is a legal question that we review de novo. United States v. Peterson,

, 837 (8th Cir. 2006).

      We have said that a reduction in sentence based on § 3553(e) may be based only
on assistance-related considerations, e.g., United States v. Plaza, 

, 930
(8th Cir. 2006); United States v. Saenz, 

, 1162 (8th Cir. 2006), but we
have twice reserved deciding whether, in light of United States v. Booker, 543 U.S.

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220 (2005), a district court may also rely on § 3553(a) to reduce a sentence further
below the statutory minimum once the government has filed a motion under
§ 3553(e). 

n.1; 

n.2. In Peterson, we
implied strongly – if we did not explicitly hold – that a district court in that situation
is limited to assistance-related considerations. The district court in Peterson imposed
a sentence below a statutory minimum after the government filed a motion under
§ 3553(e). We observed that in reducing the sentence, “the district court discussed
factors other than Peterson’s assistance,” and we concluded that a remand was
required because we could not determine “the weight the district court gave
permissible factors regarding Peterson’s 

(emphasis
added). The clear implication of Peterson is that factors unrelated to assistance were
not “permissible” considerations in determining the extent of a reduction below the
statutory minimum.

      To the extent the question remains open after Peterson (as the Plaza panel
apparently thought it was), we conclude that the text of § 3553(e) provides a clear
answer, and that Booker does not expand the district court’s authority to impose a
sentence below a statutory minimum. Section 3553(e) provides:

      (e) Limited authority to impose a sentence below a statutory
      minimum. — Upon motion of the Government, the court shall have the
      authority to impose a sentence below a level established by statute as a
      minimum sentence so as to reflect a defendant’s substantial assistance in
      the investigation or prosecution of another person who has committed an
      offense. Such sentence shall be imposed in accordance with the
      guidelines and policy statements issued by the Sentencing Commission
      pursuant to section 994 of title 28, United States Code.

       Two aspects of the text are particularly instructive. First is the title, which
states that the section provides only “limited authority” to impose a sentence below
the statutory minimum. Congress evidently wanted statutory minimum sentences to
be firmly enforced, subject only to carefully “limited” exceptions. United States v.

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Ahlers, 

, 61-62 (1st Cir. 2002). The body of § 3553(e) specifies precisely
how a sentencing court’s authority is limited. It may impose a sentence below the
statutory minimum only “so as to reflect a defendant’s substantial assistance.” 18
U.S.C. § 3553(e) (emphasis added). If a district court imposes a sentence below the
statutory minimum in part so as to reflect the history and characteristics of the
defendant, see § 3553(a)(1), then the court exceeds the limited authority granted by
§ 3553(e). The second textual sentence of § 3553(e) refers back to the penal sentence
contemplated in the first textual sentence, and thus “restricts the court’s reference to
those guidelines and policy statements that bear directly upon the desirability and
extent of a substantial assistance departure.” 

.

       Nothing in the reasoning of Booker expands the authority of a district court to
sentence below a statutory minimum. The Court’s remedial holding provided that to
cure the constitutional infirmity of the mandatory guidelines system, a district court
is authorized to consider the factors set forth in § 3553(a), and to vary from the
sentence otherwise indicated by the sentencing guidelines. But Booker did not
question the constitutionality of statutory minimum sentences, see United States v.
Rojas-Coria, 

, 874 n.4 (8th Cir. 2005), and while the Court excised
§§ 3553(b)(1) and 3742(e) from the Code, § 3553(e) was unmentioned in the opinion.
The Court deviated from the mandatory guidelines system adopted by Congress only
insofar as the deviation was necessary to make the remaining advisory system
consistent with the Sixth Amendment. 

. Because statutory
minimum sentences remain constitutional, and it is constitutional for Congress to limit
a court’s authority to sentence below such minimums, the remedial holding of Booker
does not impact the pre-existing limitations embodied in § 3553(e).

      In this case, the district court reduced Williams’s sentence below the statutory
minimum in two increments – one based on substantial assistance and one based on
other factors. Because the second increment was impermissible for the reasons



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explained above, we vacate the sentence and remand for resentencing consistent with
this opinion.
                           ______________________________




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