United States Court of Appeals
                            FOR THE EIGHTH CIRCUIT
                                   ___________

                                Nos. 06-2284/2497
                                  ___________

United States of America,           *
                                    *
     Appellee/Cross-Appellant,      *
                                    * Appeals from the United States
     v.                             * District Court for the Northern
                                    * District of Iowa.
Rodney Jay Jensen,                  *
                                    *
     Appellant/Cross-Appellee.      *
                               ___________

                             Submitted: January 9, 2007
                                Filed: June 28, 2007(Corrected: July 5, 2007)
                                 ___________

Before COLLOTON and GRUENDER, Circuit Judges, and GOLDBERG, Judge.1
                         ___________

COLLOTON, Circuit Judge.

       Rodney Jensen pled guilty to conspiring to distribute more than 500 grams of
methamphetamine, and to possessing with intent to distribute more than 500 grams
of methamphetamine. Because he had sustained two previous convictions for drug
trafficking offenses, Jensen was subject to a mandatory term of life imprisonment,
pursuant to 21 U.S.C. §§ 841(b)(1)(A) and 851. As part of his plea agreement, Jensen
cooperated with law enforcement in the investigation and prosecution of other


      1
       The Honorable Richard W. Goldberg, Judge, United States Court of
International Trade, sitting by designation.
persons, and the government moved the district court, pursuant to USSG § 5K1.1 and
18 U.S.C. § 3553(e), to reduce Jensen’s sentence from life imprisonment to a term of
years.

      The district court granted the motions and reduced Jensen’s sentence to 180
months’ imprisonment. The court specified that, for purposes of its analysis, it
equated life imprisonment with a term of 360 months’ imprisonment. The court then
reduced that sentence in two increments: first, to 216 months’ imprisonment based
on Jensen’s substantial assistance in the investigation and prosecution of others, and
second, to 180 months’ imprisonment based on other factors set forth in 18 U.S.C.
§ 3553(a).

       Neither party is happy with the sentence. Jensen argues that because he was 59
years old at the time of sentencing, and his personal life expectancy was thus less than
360 months, the district court should have adopted a shorter term of imprisonment as
a “starting point” for analysis, and then reduced his sentence from there. The
government contends that because the sentencing table published in the United States
Sentencing Guidelines Manual extends as high as 405 months’ imprisonment, and
because the Sentencing Commission has defined life sentences as 470 months in its
annual Sourcebook for Federal Sentencing Statistics, the district court should have
used a greater term of imprisonment as the starting point for its analysis. The
government also argues that the district court was not permitted to reduce Jensen’s
sentence based on factors set forth in 18 U.S.C. § 3553(a) that are unrelated to
assistance.

      Taking the last point first, we agree with the government that the district court’s
reduction of sentence from 216 months to 180 months was contrary to law. When the
government files a motion under 18 U.S.C. § 3553(e), the court has “limited
authority” to sentence a defendant below the statutory minimum. In United States v.
Williams, 

(8th Cir. 2007), we held that this reduction in sentence below

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the statutory minimum must reflect only the defendant’s substantial assistance. 

The court may not reduce the sentence further based on factors unrelated to
assistance, such as those set forth in 18 U.S.C. § 3553(a), because such a reduction
exceeds the limited authority granted by § 3553(e). 

court did not have
the benefit of our decision in Williams, but it is now clear that the second increment
in the court’s reduction was not permissible.

        The remaining question is whether the district court abused its discretion in
reducing Jensen’s sentence from life imprisonment to 216 months. Jensen says the
court should have analyzed the reduction by equating “life” with Jensen’s actual life
expectancy of 20.49 years, and then reducing the sentence from there based on
substantial assistance. We reject Jensen’s contention as inconsistent with the structure
of the advisory guidelines. Departures and reductions based on substantial assistance
are to be considered in the context of the advisory guidelines system, see United States
v. Saenz, 

, 1162 (8th Cir. 2005), and that system contemplates a range
of incremental punishments ranging from 0-6 months’ imprisonment up to Jensen’s
pre-assistance sentence of life imprisonment. USSG Ch. 5, Pt. A (sentencing table).
These punishments are fixed without regard to the offender’s life expectancy, and
many offenders – including offenders of Jensen’s age who are viewed by the
Sentencing Commission as less serious than Jensen – are subject to terms of
imprisonment of greater than 20.49 years. Thus, it would be anomalous to treat
Jensen as the equivalent of an offender who is subject to a term of only 20 years under
the guidelines, when other less serious offenders who earn sentence reductions are
subject to a higher “starting point” in the sentencing scheme.

      The government, on the other hand, contends the district court should have
analyzed the reduction by equating “life” with a term of 470 months’ imprisonment.
We did hold in United States v. Keller, 

(8th Cir. 2005), that a district
court’s use of 470 months as a “starting point” was not “in error,” 

but we
are not convinced that it must be the starting point in every case. Cf. United States v.

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Selby, 184 F. App’x 589, 591 (8th Cir. 2006) (per curiam) (unpublished) (holding in
post-Keller decision that district court did not err in using 405 months as a starting
point for departure from life imprisonment). The 470-month figure is derived from
the Sentencing Commission’s Sourcebook of Federal Sentencing Statistics, where the
Commission has explained that “to reflect life expectancy of federal criminal
defendants more precisely and to provide more accurate length of imprisonment
information, life sentences are now defined as 470 months.” United States Sentencing
Commission, 2005 Sourcebook of Federal Sentencing Statistics, App. A (Post-
Booker), at 2. There is no indication that the Commission’s selection of 470 months
was a policy judgment about the incremental punishment that should accompany an
increase in an offender’s offense level from Level 42 (which carries a minimum
advisory sentence of 360 months) to Level 43 (which prescribes life imprisonment).
Prior to fiscal year 1993, the Commission defined life imprisonment as 360 months,
and the change to 470 months was based purely on empirical data concerning the life
span of present-day inmates. 

doubtful about the district court’s use of 360 months’ imprisonment as
a starting point, because that figure represents no incremental punishment from Level
42 to Level 43. In addition, the guideline sentencing table contemplates sentencing
ranges that go as high as 405 months, so it would be odd to equate the maximum
sentence of life with a lesser term of 360 months. See Selby, 184 F. App’x at 591.
Nonetheless, while the parties are fixated on selecting a specific number of months as
a starting point, we find that exercise unnecessary to resolve this case. A starting
point expressed in a number of months is essential to the analysis only if one accepts
the United States Attorney’s view that reductions must be measured as a percentage
of the otherwise applicable sentence. Percentages are not the only way to evaluate the
reasonableness of a reduction, and they can sometimes be unhelpful or even
misleading. Cf. United States v. Maloney, 

, 668-69 (8th Cir. 2006)
(discussing the issue in the context of variances under 18 U.S.C. § 3553(a)).



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       In this case, where the Sentencing Commission has not placed a number on
“life” imprisonment for the purpose of prescribing an incremental punishment, we
think it more helpful to view the district court’s reduction in terms of the incremental
guideline ranges in the Sentencing Commission’s sentencing table. Cf. 

A
sentence of life imprisonment corresponds to offense level 43 as a starting point, see
United States v. Nelson, No. 05-3624, 

, at *2 (7th Cir. June 21,
2007), and a reduction from life imprisonment to a term of 216 months amounts to a
decrease of six guideline ranges. This measure of the reduction is illustrated most
clearly in criminal history category I, where “life” corresponds to offense level 43, and
216 months’ imprisonment is within the sentencing range at offense level 37 – a
difference of six offense levels. Jensen’s criminal history score placed him in criminal
history category II, but the government does not urge that a reduction from a statutory
minimum of life imprisonment to 216 months should be viewed as a greater reduction
for a defendant in category II than for a defendant in category I. Indeed, the
government’s percentage-based approach treats equally all defendants facing a
particular term of imprisonment, regardless of the applicable criminal history
category. Likewise, we do not think it necessary to view the difference between level
42, category II, and level 41, category II, both of which carry a sentencing range of
“360-life,” as a “reduction” for purposes of determining whether the district court
abused its discretion in this context. See Nelson, 

, at *1 (recounting
that the government, in recommending reduction of four sentencing guideline ranges
from life imprisonment and offense level 43 for a defendant in category VI, asked the
district court “to ‘clump’ the six guideline ranges of ‘360-life’ under category VI
(offense levels 42 to 37) ‘together into one,’” and that the recommended sentence was
within the range corresponding to offense level 34).

       A reduction of six guideline ranges is significant in the context of an advisory
guideline system where the degree of most aggravating and mitigating adjustments is
two, three, or four offense levels. 

. But it is less dramatic
than other reductions that we have viewed as so great as to require exceptional facts

                                          -5-
to justify them. See United States v. Coyle, 

, 1193-94 (8th Cir. 2005)
(14-level reduction); United States v. Dalton, 

, 1033 (8th Cir. 2005)
(12-level reduction); 

(11-level reduction); United States v.
Haack, 

, 1005 (8th Cir. 2005) (7-level reduction); see also United States
v. Burns, 

, 831 (8th Cir. 2006) (Wollman, J., dissenting) (disagreeing
with panel decision affirming a 10-level reduction), vacated and reh’g en banc
granted, Nos. 04-2901/2933 (8th Cir. May 18, 2006); cf. United States v. Pizano, 

, 997 (8th Cir. 2005) (affirming 12-level reduction). The district court here
determined that Jensen’s assistance was not “extraordinary” within the meaning of our
cases, and that the reduction in sentence should be less than fifty percent of a starting
point expressed in a number of months. (S. Tr. II at 28-29); cf. 

(stating that “an extraordinary reduction must be supported by extraordinary
circumstances,” and citing favorably an observation that a 50 percent downward
departure was an “extraordinary sentence reduction”).

      The record here shows that Jensen was debriefed extensively by law
enforcement agents concerning a substantial methamphetamine conspiracy, and that
he was a prospective witness in the sentencing proceeding of a co-conspirator. (The
conspirator ultimately stipulated to an enhancement as Jensen waited to testify).
Jensen also identified the conspirators’ source of supply in Arizona – a major figure
in the conspiracy – and testified in the grand jury in preparation for what the
government characterized as a “probable future indictment.” (S. Tr. II at 7). The
government stipulated that Jensen’s assistance was timely, complete, and truthful.
While the reduction here is generous, and at or near the limit of what we could view
as reasonable based on this level of assistance, we hold that the district court’s
reduction of Jensen’s sentence by the equivalent of six guideline ranges was not an
abuse of discretion.

     For these reasons, we vacate the judgment of the district court and remand for
imposition of a sentence of 216 months’ imprisonment.
                        ______________________________


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