                           PUBLISHED

UNITED STATES COURT OF APPEALS
                FOR THE FOURTH CIRCUIT


UNITED STATES OF AMERICA,              
                 Plaintiff-Appellee,
                 v.                             No. 02-4956
ANTHONY K. ROUSE,
             Defendant-Appellant.
                                       
           Appeal from the United States District Court
      for the Western District of Virginia, at Charlottesville.
           James H. Michael, Jr., Senior District Judge.
                           (CR-01-15)

                      Argued: January 21, 2004

                      Decided: March 26, 2004

         Before WILKINS, Chief Judge, and NIEMEYER
                 and TRAXLER, Circuit Judges.



Affirmed by published opinion. Chief Judge Wilkins wrote the opin-
ion in which Judge Niemeyer and Judge Traxler joined.


                            COUNSEL

ARGUED: J. Lloyd Snook, III, SNOOK & HAUGHEY, P.C., Char-
lottesville, Virginia, for Appellant. Nancy Spodick Healey, Assistant
United States Attorney, Charlottesville, Virginia, for Appellee. ON
BRIEF: John L. Brownlee, United States Attorney, Charlottesville,
Virginia, for Appellee.
2                      UNITED STATES v. ROUSE
                             OPINION

WILKINS, Chief Judge:

   Anthony K. Rouse appeals the sentence imposed on him by the dis-
trict court following his plea of guilty to conspiracy to distribute
cocaine base, see 21 U.S.C.A. § 846 (West 1999). Rouse argues that
the district court was required by United States Sentencing Guidelines
Manual § 5G1.3(b) (2000) to impose his federal sentence to be served
concurrently with a state sentence Rouse was serving for a previous
drug distribution conviction. We affirm.

                                  I.

   Rouse was involved in a drug distribution conspiracy in Orange
County, Virginia, between 1999 and late 2000. The primary object of
the conspiracy was the distribution of cocaine base. On April 6, 2000,
Rouse sold one third of a gram of cocaine base to an undercover offi-
cer ("the April 6 drug sale"). In April 2001, Rouse pleaded guilty in
state court to distribution of cocaine and was sentenced to 13 years
imprisonment with six and one-half years suspended.

   In June 2001, Rouse pleaded guilty in federal court to one count
of conspiracy to distribute 50 or more grams of cocaine base. Regard-
ing the April 6 drug sale, the plea agreement provided:

       The United States stipulates and agrees that my recent
    conviction in April 2001 for drug distribution in Orange
    County, Virginia, was for a distribution that was a part of
    the conspiracy to which I am now pleading guilty in accor-
    dance with this plea agreement.

J.A. 14. The plea agreement also contained a stipulation by Rouse that
"the total drug weight for which I should be held accountable . . . is
at least 50 grams but less than 150 grams of cocaine base, unless the
presentence investigation shows a lesser amount." Id. at 13-14.

  Consistent with the plea agreement, the presentencing report (PSR)
predicated Rouse’s base offense level on a drug quantity of between
                         UNITED STATES v. ROUSE                            3
50 and 150 grams of cocaine base. See U.S.S.G. § 2D1.1(c)(4). How-
ever, because Rouse is a career offender, his offense level was
adjusted to level 37 based not on drug quantity, but rather on the stat-
utory maximum penalty of life imprisonment for the offense of con-
viction.* See id. § 4B1.1(A). After three levels were subtracted for
acceptance of responsibility, Rouse’s adjusted offense level was 34.
This offense level, combined with the mandatory Criminal History
Category VI, see id. § 4B1.1, resulted in a guideline range of 262 to
327 months imprisonment. Rouse raised no objections to the PSR.

   At sentencing, the district court granted the Government’s motion
for a downward departure based on Rouse’s substantial assistance, see
id. § 5K1.1, and imposed the statutory minimum sentence of ten
years. Following the imposition of this sentence, Rouse’s counsel
asked whether Rouse would receive any credit on his federal sentence
for the state sentence Rouse was serving for the April 6 drug sale. The
district court responded, "The Court has the authority to direct that the
sentence run consecutively or concurrently . . . . [I]n this case, it does
seem appropriate to the Court that he serve these sentences consecu-
tively . . . ." J.A. 38. Counsel did not object.

   Rouse now appeals, arguing only that the district court was
required to order that his federal sentence be served concurrently with
his state sentence.

                                     II.

   Section 5G1.3 of the Guidelines provides instructions concerning
the imposition of sentence when the defendant is subject to an undis-
charged term of imprisonment. At the time of Rouse’s sentencing,
§ 5G1.3 provided in pertinent part:

   *Rouse does not dispute that he was properly classified as a career
offender, nor does he contend that his conviction for the April 6 drug sale
was one of the convictions on which his career offender status was predi-
cated. Compare U.S.S.G. § 4B1.1 (providing that "[a] defendant is a
career offender if," inter alia, "the defendant has at least two prior felony
convictions of either a crime of violence or a controlled substance
offense") with J.A. 60 (noting that the conviction for the April 6 drug
sale was not awarded any criminal history points because of its relation
to the instant offense).
4                      UNITED STATES v. ROUSE
    (b) If . . . the undischarged term of imprisonment resulted
        from offense(s) that have been fully taken into account
        in the determination of the offense level for the instant
        offense, the sentence for the instant offense shall be
        imposed to run concurrently to the undischarged term
        of imprisonment.

    (c) (Policy Statement) In any other case, the sentence for
        the instant offense may be imposed to run concur-
        rently, partially concurrently, or consecutively to the
        prior undischarged term of imprisonment to achieve a
        reasonable punishment for the instant offense.

U.S.S.G. § 5G1.3(b), (c). Rouse contends that the April 6 drug sale
was "fully taken into account" in his sentencing for the instant offense
and thus that the district court was required by § 5G1.3(b) to impose
a concurrent sentence.

   The Government contends, and we agree, that Rouse did not ade-
quately raise this issue before the district court. While Rouse’s coun-
sel did inquire of the court whether the federal sentence would be
served concurrently or consecutively to the state sentence, he neither
cited § 5G1.3(b) nor argued that the court was required to impose a
concurrent sentence. Therefore, our review is for plain error. See Fed.
R. Crim. P. 52(b); United States v. Olano, 507 U.S. 725, 731-32
(1993). To establish plain error, Rouse must show that an error
occurred, that the error was plain, and that the error affected his sub-
stantial rights. See Olano, 507 U.S. at 732. Even if Rouse makes this
three-part showing, correction of the error remains within our discre-
tion, which we "should not exercise . . . unless the error ‘seriously
affect[s] the fairness, integrity or public reputation of judicial pro-
ceedings.’" Id. (quoting United States v. Young, 470 U.S. 1, 15 (1985)
(alteration in original)).

                                  A.

   Before turning to the application of the plain error standard, we
pause for a housekeeping matter. Effective November 1, 2003,
§ 5G1.3 and the accompanying commentary were amended. As
amended, § 5G1.3(b) provides as follows:
                       UNITED STATES v. ROUSE                        5
       If subsection (a) does not apply, and a term of imprison-
    ment resulted from another offense that is relevant conduct
    to the instant offense of conviction . . . and that was the
    basis for an increase in the offense level for the instant
    offense under Chapter Two (Offense Conduct) or Chapter
    Three (Adjustments), the sentence for the instant offense
    shall be imposed as follows:

         (1) the court shall adjust the sentence for any
         period of imprisonment already served on the
         undischarged term of imprisonment if the court
         determines that such period of imprisonment will
         not be credited to the federal sentence by the
         Bureau of Prisons; and

         (2) the sentence for the instant offense shall be
         imposed to run concurrently to the remainder of
         the undischarged term of imprisonment.

U.S.S.G. § 5G1.3(b) (2003), available at http://www.ussc.gov/
2003guid/5g1_3.htm. Clarifying amendments are relevant in our con-
struction of previous versions of the guidelines. See United States v.
Butner, 277 F.3d 481, 489 (4th Cir. 2002). We therefore must con-
sider whether the amendment of § 5G1.3(b) is clarifying or substan-
tive.

   A clarifying amendment "changes nothing concerning the legal
effect of the guidelines, but merely clarifies what the Commission
deems the guidelines to have already meant." United States v. Capers,
61 F.3d 1100, 1109 (4th Cir. 1995) (internal quotation marks omit-
ted). In contrast, "[s]ubstantive amendments typically reflect new pol-
icy choices by the Commission." United States v. Goines, 357 F.3d
469, 2004 WL 144119, at *4 (4th Cir. Jan. 28, 2004). Our primary
guide in determining whether an amendment is clarifying or substan-
tive is the "purpose and effect" of the amendment. Capers, 61 F.3d
at 1110. The Commission’s characterization of an amendment as clar-
ifying or substantive is relevant but not conclusive, for otherwise the
Commission would be able to enact substantive amendments under
the guise of mere clarification. See id.
6                       UNITED STATES v. ROUSE
   The Commission has characterized the amendment of § 5G1.3(b)
and its accompanying commentary as clarifying. See U.S.S.G. App.
C, amend. 660. Nevertheless, application of the principles outlined
above makes it clear that the amendment is substantive. Prior to the
amendment, a prior offense could be "fully taken into account" even
if inclusion of the offense as relevant conduct did not effect a change
in the defendant’s offense level. Compare U.S.S.G. § 5G1.3, com-
ment. (n.2) (providing an example in which the offense of conviction
involved the sale of 30 grams of cocaine and "the defendant is held
accountable for the sale of an additional 15 grams of cocaine, an
offense for which the defendant has been convicted and sentenced in
state court"), with U.S.S.G. § 2D1.1(c)(13) (providing a base offense
level of 14 for "[a]t least 25 G but less than 50 G of Cocaine"). The
amended guideline, however, requires the conduct underlying the
prior conviction to have been "the basis for an increase in the offense
level for the instant offense." U.S.S.G. § 5G1.3(b) (2003). The
amendment thus "works a substantive change in the operation of the
guideline," Capers, 61 F.3d at 1110, and cannot be considered clarify-
ing.

                                   B.

   Turning to review of the issue before us, we first must decide
whether there was error. The question on appeal—whether the April
6 drug sale was "fully taken into account in determining the offense
level for the instant offense"—involves two subsidiary questions: (1)
What rule applies in determining whether a prior offense has been
fully taken into account? and (2) How does that rule apply here?
These are both issues of guideline interpretation subject to de novo
review. See Elliott v. United States, 332 F.3d 753, 761 (4th Cir.), cert.
denied, 124 S. Ct. 487 (2003).

   In interpreting a guideline, ordinary rules of statutory construction
apply. See United States v. Stokes, 347 F.3d 103, 105 (4th Cir. 2003).
These rules require us to give the guideline its plain meaning, as
determined by examination of its "language, structure, and purpose."
United States v. Horton, 321 F.3d 476, 479 (4th Cir.) (internal quota-
tion marks omitted), cert. denied, 124 S. Ct. 98 (2003). We must also
examine the commentary accompanying the guideline, which "is
authoritative unless it violates the Constitution or a federal statute, or
                        UNITED STATES v. ROUSE                         7
is inconsistent with, or a plainly erroneous reading of, that guideline."
Stinson v. United States, 508 U.S. 36, 38 (1993).

                                   1.

   The purpose of § 5G1.3(b) is essential to understanding its lan-
guage and deriving a rule for its application. See United States v. Kim-
ble, 107 F.3d 712, 714 (9th Cir. 1997). Generally speaking,
§ 5G1.3(b) addresses the situation in which a defendant is prosecuted
in more than one jurisdiction for related conduct. See Witte v. United
States, 515 U.S. 389, 404 (1995). As the Supreme Court has
explained,

    There are often valid reasons why related crimes committed
    by the same defendant are not prosecuted in the same pro-
    ceeding, and § 5G1.3 of the Guidelines attempts to achieve
    some coordination of sentences imposed in such situations
    with an eye toward having such punishments approximate
    the total penalty that would have been imposed had the sen-
    tences for the different offenses been imposed at the same
    time (i.e., had all of the offenses been prosecuted in a single
    proceeding).

Id. at 404-05. Phrased differently, § 5G1.3(b) prevents the "double
counting" that occurs when "separate, non-offense conduct could,
absent operation of this sub-section, otherwise be the basis both (1)
for sentencing defendant as if that conduct had been part of the offen-
se(s) of conviction, and (2) for additional punishment of that same
conduct in another, and separate, criminal proceeding." United States
v. Garcia-Hernandez, 237 F.3d 105, 109 (2d Cir. 2000). Section
5G1.3 thereby "operates to mitigate the possibility that the fortuity of
two separate prosecutions will grossly increase a defendant’s sen-
tence." Witte, 515 U.S. at 405.

   In view of the purpose of § 5G1.3(b), we agree with the Second
Circuit that the provision applies—i.e., that a prior offense has been
"fully taken into account in the determination of the offense level for
the instant offense"—at least when conduct underlying a prior convic-
tion is considered as relevant conduct. See Garcia-Hernandez, 237
F.3d at 109; Webster’s Encyclopedic Unabridged Dictionary of the
8                      UNITED STATES v. ROUSE
English Language 13 (2001) (defining "take account of" as "to make
allowance for; consider"). For example, when a defendant being sen-
tenced for a federal drug offense is held accountable, under relevant
conduct principles, for a sale of narcotics that was prosecuted in state
court, § 5G1.3(b) applies. See U.S.S.G. § 5G1.3, comment. (n.2). In
contrast, when conduct for which a defendant is serving an undis-
charged term of imprisonment is employed in calculating the defen-
dant’s offense level but is not relevant conduct to the instant offense,
§ 5G1.3(b) may well not apply. See Garcia-Hernandez, 237 F.3d at
110 (holding that enhancement for prior aggravated felony conviction
did not require application of § 5G1.3(b) because the guidelines did
not treat the prior offense as though it had been prosecuted in the
same proceeding).

                                   2.

   Having determined the manner in which § 5G1.3(b) is to be
applied, we now turn to its application in this case. There can be no
question that the April 6 drug sale is relevant conduct to the instant
offense of conspiracy to distribute cocaine base. See U.S.S.G.
§ 1B1.3(a) (including as relevant conduct "all acts and omissions
committed . . . by the defendant . . . that occurred during the commis-
sion of the offense of conviction"). Moreover, the parties appear to
agree that, as a factual matter, the quantity of cocaine base involved
in the April 6 drug sale is included in the larger quantity of drugs
attributed to Rouse for sentencing purposes. And, the probation offi-
cer employed this drug quantity in calculating the base offense level
for Rouse’s offense.

   If these were the only considerations, there would be no question
that the April 6 drug sale was "fully taken into account." However,
because Rouse was sentenced as a career offender, his ultimate
offense level was based on the statutory maximum, not on drug quan-
tity. We think this makes no difference. The calculation of an offense
level based on relevant conduct is a necessary step in applying the
career offender guideline. See U.S.S.G. § 4B1.1 (providing for the
application of an offense level based on the offense statutory maxi-
mum if that level "is greater than the offense level otherwise applica-
ble"). Therefore, the April 6 drug sale was in fact taken into account
in determining the offense level applicable to Rouse, and § 5G1.3(b)
                       UNITED STATES v. ROUSE                         9
applies. Accordingly, the district court erred in not applying
§ 5G1.3(b).

                                  C.

   We next must decide whether the error was plain. To be plain, an
error must be "clear" or "obvious," Olano, 507 U.S. at 734 (internal
quotation marks omitted), at least by the time of appeal, see Johnson
v. United States, 520 U.S. 461, 468 (1997). An error is clear or obvi-
ous "when the settled law of the Supreme Court or this circuit estab-
lishes that an error has occurred. In the absence of such authority,
decisions by other circuit courts of appeals are pertinent to the ques-
tion of whether an error is plain." United States v. Neal, 101 F.3d 993,
998 (4th Cir. 1996) (internal quotation marks & citation omitted).

   The Supreme Court has not yet addressed the question raised by
Rouse’s appeal, and prior to our decision today, neither had any deci-
sion of this court. And, it appears that the Second Circuit might reach
a conclusion different from ours if confronted with the same facts. See
United States v. Williams, 260 F.3d 160, 166-68 (2d Cir. 2001) (refus-
ing to apply § 5G1.3(b) when prior offense conduct was considered
in determining the offense level but the district court imposed the sen-
tenced stipulated to by the parties pursuant to Federal Rule of Crimi-
nal Procedure 11(c)(1)(C); holding that "the prior offense must have
been actually accounted for by the district court in calculating the
defendant’s offense level"). Therefore, the error was not plain. Cf.
United States v. Alli-Balogun, 72 F.3d 9, 12 (2d Cir. 1995) (per
curiam) (stating that "we do not see how an error can be plain error
when the Supreme Court and this court have not spoken on the sub-
ject, and the authority in other circuit courts is split").

                                  III.

   For the reasons set forth above, we affirm the sentence imposed by
the district court.

                                                           AFFIRMED
