                 FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA,                No. 04-50226
                Plaintiff-Appellee,
                                            D.C. No.
               v.
                                         CR-03-01243-
ERIC JAMES THORNTON, JR., aka                JFW-2
Seal B,
                                           OPINION
             Defendant-Appellant.
                                      
       Appeal from the United States District Court
          for the Central District of California
        John F. Walter, District Judge, Presiding

                  Argued and Submitted
          October 19, 2005—Pasadena, California

                   Filed April 17, 2006

 Before: Cynthia Holcomb Hall, Diarmuid F. O’Scannlain,
          and Richard A. Paez, Circuit Judges.

                  Opinion by Judge Paez




                           4245
                 UNITED STATES v. THORNTON             4247


                        COUNSEL

Jerry Sies, Los Angeles, California, for the defendant-
appellant.

Becky S. Walker and Carole C. Peterson, Office of the United
States Attorney, Los Angeles, California, for the plaintiff-
appellee.
4248                UNITED STATES v. THORNTON
                               OPINION

PAEZ, Circuit Judge:

   This case requires us to decide whether a conviction under
California Vehicle Code section 23152(b) for driving with a
blood alcohol level of 0.08 or higher is a conviction for an
offense “similar” to driving under the influence, such that it
must be included in a defendant’s criminal history calculation
pursuant to U.S.S.G. § 4A1.2 cmt. n.5.1 We hold that it is.

                          I.   Background

   Eric James Thornton, Jr. pleaded guilty to violating 21
U.S.C. § 846 (conspiracy to distribute a controlled substance).
Thornton signed a written plea agreement that contemplated,
but did not guarantee, application of U.S.S.G. § 5C1.2, known
as the “safety valve” provision. Pursuant to this provision, “in
the case of an offense under 21 U.S.C. § . . . 846 . . . , the
court shall impose a sentence in accordance with the applica-
ble guidelines without regard to any statutory minimum sen-
tence, if the court finds that the defendant meets” certain
criteria. U.S.S.G. § 5C1.2(a). One of those criteria is that “the
defendant does not have more than 1 criminal history point.”
Id. § 5C1.2(a)(1). If Thornton did not satisfy the criteria for
application of the safety valve, he faced a mandatory mini-
mum sentence of 120 months in prison followed by five years
of supervised release. See 21 U.S.C. § 841(b).

   Thornton’s Presentence Report (“PSR”) recommended that
one criminal history point be added to his criminal history
score for his prior sentence of probation for violating Califor-
nia Vehicle Code section 23152(b). See U.S.S.G. § 4A1.1(c).
The PSR also recommend that two criminal history points be
added for committing the § 846 offense while under that sen-
  1
   All references are to the November 2003 version of the United States
Sentencing Guidelines.
                      UNITED STATES v. THORNTON                          4249
tence of probation. See id. § 4A1.1(d). These recommenda-
tions resulted in a total criminal history score of three points,
which placed Thornton in Criminal History Category II. The
three points also rendered him ineligible for safety valve
relief.

   Thornton objected to the PSR, arguing that his conviction
for driving with a blood alcohol level of 0.08 or higher was
a conviction for a minor traffic infraction or public intoxica-
tion, and should not be counted in his criminal history calcu-
lation. See id. § 4A1.2(c)(2) (“Sentences for [minor traffic
infractions and public intoxication] and offenses similar to
them, by whatever name they are known, are never counted
. . . .”). Under Thornton’s theory, the criminal history point
attributable to his prior California conviction, as well as the
two criminal history points that depended on that earlier con-
viction, were erroneously counted in determining his criminal
history score. Thornton therefore argued that he had a crimi-
nal history score of zero and was eligible for the safety valve.
If the district court had agreed, it would have been permitted
to sentence Thornton to fewer than the 120 months required
by the mandatory minimum statute. See id. § 5C1.2.2

   The district court, however, rejected Thornton’s argument,
found him ineligible for U.S.S.G. § 5C1.2’s safety valve
relief, and imposed the mandatory minimum sentence. Thorn-
ton timely appealed.
   2
     In the written plea agreement, the parties stipulated that Thornton satis-
fied three of the five criteria for invoking the safety valve, specifically
U.S.S.G. §§ 5C1.2(a)(2), (3), and (4). Criterion (5) requires that a defen-
dant provide to the government any information and evidence he has
regarding the offense. U.S.S.G. § 5C1.2(a)(5). In addressing potential
safety valve eligibility, the PSR stated only that Thornton did not satisfy
criterion (1), i.e., not having more than one criminal history point. The
Government did not argue in the district court, and has not argued to this
court, that Thornton failed to satisfy criterion (5) as well. The parties
appear in agreement that Thornton’s safety valve eligibility turns on
whether he satisfies criterion (1).
4250                UNITED STATES v. THORNTON
           II.   Jurisdiction and Standards of Review

   We have jurisdiction over Thornton’s appeal pursuant to 18
U.S.C. § 3742(a) and 28 U.S.C. § 1291. Although the Sen-
tencing Guidelines are no longer mandatory, we must still
consider whether the district court properly applied the Guide-
lines; if it did not, and if the error was not harmless, we will
remand to the district court for resentencing. See United
States v. Cantrell, 433 F.3d 1269, 1279 (9th Cir. 2006).

  We review de novo the district court’s interpretation of the
Sentencing Guidelines. United States v. Ramirez, 347 F.3d
792, 797 (9th Cir. 2003). We also review de novo “[w]hether
a prior adjudication falls within the scope of the Sentencing
Guidelines.” Id. (internal quotation marks omitted).

                        III.   Discussion

A.     California Vehicle Code section 23152(b) proscribes
       conduct that is “similar” to driving while intoxicated or
       under the influence.

   In general, under the Sentencing Guidelines, a district court
is required to add one point to a defendant’s criminal history
score for a prior conviction where, as in Thornton’s case, the
defendant’s sentence was suspended and he was placed on
probation. See U.S.S.G. §§ 4A1.1(c), 4A1.2(a)(3). The Guide-
lines, however, contain certain exceptions. Sentences for
minor traffic infractions, public intoxication, or similar
offenses are not counted. Id. § 4A1.2(c)(2). Sentences for
driving under the influence, on the other hand, explicitly are
counted. According to the commentary accompanying the
Guidelines, “[c]onvictions for driving while intoxicated or
under the influence (and similar offenses by whatever name
they are known) are counted. Such offenses are not minor
                      UNITED STATES v. THORNTON                        4251
traffic infractions within the meaning of § 4A1.2(c).” Id.
§ 4A1.2 cmt. n.5.3

   [1] The district court added one point to Thornton’s crimi-
nal history score for a prior conviction under California Vehi-
cle Code section 23152(b), and an additional two points
because Thornton committed the § 846 offense while on pro-
bation for that prior conviction. Section 23152 is California’s
“driving under the influence” statute. Subsection (a) makes it
“unlawful for any person who is under the influence of any
alcoholic beverage . . . to drive a vehicle,” and subsection (b)
makes it “unlawful for any person who has 0.08 percent or
more, by weight, of alcohol in his or her blood to drive a vehi-
cle.” Cal. Veh. Code § 23152(a), (b).

   [2] A conviction under subsection (b) is not the same as a
conviction for driving under the influence because the State
is not required to prove that a defendant’s driving was
impaired to convict him of section 23152(b)—only that he
had a specified blood alcohol level. See Hamilton v. Gourley,
126 Cal. Rptr. 2d 652, 658 (Ct. App. 2003) (“[T]o obtain a
conviction under section 23152, subdivision (b), the prosecu-
tion has no burden to prove that the defendant’s driving abil-
ity was impaired. The trier of fact need not determine whether
a defendant was ‘driving under the influence,’ only whether
he had the specified BAC level. A conviction for driving with
a .08 percent BAC level thus neither entails nor requires a
finding of impairment.” (citation omitted)); see also People v.
Bransford, 884 P.2d 70, 73-74 (Cal. 1994) (en banc) (stating
that the prosecution need not prove a defendant was impaired,
intoxicated, or under the influence to convict him under sec-
  3
    “ ‘[C]ommentary in the Guidelines Manual that interprets or explains
a guideline is authoritative unless it violates the Constitution or a federal
statute, or is inconsistent with, or a plainly erroneous reading of, that
guideline.’ ” United States v. Mendoza-Morales, 347 F.3d 772, 775 n.3
(9th Cir. 2003) (alteration in original) (quoting Stinson v. United States,
508 U.S. 36, 38 (1993)).
4252              UNITED STATES v. THORNTON
tion 23152(b)). Because Thornton’s conviction, on its face,
does not permit the conclusion that he drove while under the
influence of alcohol, Thornton urges us to hold that U.S.S.G.
§ 4A1.2 cmt. n.5 is inapplicable, and that a conviction under
section 23152(b) is analogous to a conviction for a “minor
traffic infraction[ ],” which is excluded from a defendant’s
criminal history score. U.S.S.G. § 4A1.2(c)(2).

   [3] As Thornton correctly notes, the Guidelines are silent
about whether a conviction for driving with a specified blood
alcohol level, as opposed to driving under the influence, qual-
ifies as a minor traffic infraction. According to Thornton,
because the Guidelines are silent on this issue, in order to
increase his criminal history score based on the section
23152(b) conviction, the district judge implicitly made a fac-
tual finding that Thornton was driving under the influence of
alcohol during his commission of the prior crime, in violation
of Apprendi v. New Jersey, 530 U.S. 466 (2000). Thornton
claims that this factual finding violates his Sixth Amendment
and due process rights because it adds an element to subsec-
tion (b), i.e., impaired driving, that the State was never
required to prove to a jury beyond a reasonable doubt.

   [4] We disagree. Subsection 23152(b) falls squarely within
the language of U.S.S.G. § 4A1.2 cmt. n.5, which states that
“[c]onvictions for driving while intoxicated or under the influ-
ence (and similar offenses by whatever name they are known)
are counted. Such offenses are not minor traffic infractions
within the meaning of § 4A1.2(c).” U.S.S.G. § 4A1.2 cmt. n.5
(emphasis added). Although Thornton is correct that the State
did not need to prove that his driving was impaired to convict
him of violating section 23152(b), it does not follow that a
violation of section 23152(b) is a minor traffic infraction.
Quite clearly, section 23152(b) proscribes conduct “similar”
to driving under the influence. A conviction under California
Vehicle Code section 23152(b) is therefore a conviction for
an offense “similar” to driving under the influence.
                  UNITED STATES v. THORNTON                 4253
   [5] Aside from the inherent logic of this conclusion, we
find support for it in the California statutory scheme. Under
California law, driving with a blood alcohol level of 0.08 per-
cent or higher creates a rebuttable presumption that a defen-
dant has violated section 23152(a) (driving under the
influence). See Cal. Veh. Code § 23610(a)(3). Additionally,
the penalty for a violation of section 23152 is the same,
regardless of the subsection under which a defendant is con-
victed. See id. § 23536. These statutes leave us with little
doubt that there is sufficient similarity between subsections
(a) and (b) of California’s “driving under the influence” law
to require inclusion of a conviction under section 23152(b) in
a defendant’s criminal history score.

   [6] The conclusion that a conviction for driving with a
specified blood alcohol content is “similar” to a conviction for
driving under the influence and includable in a defendant’s
criminal history calculation is in accord with the law of the
only other circuit to address this precise issue in a published
opinion. In United States v. Strange, 102 F.3d 356 (8th Cir.
1996), the Eighth Circuit held that a criminal history point
was properly added to Strange’s criminal history score for the
offense of driving a motor vehicle with an excessive blood
alcohol content. See id. at 363; cf. United States v. Walling,
974 F.2d 140, 142 (10th Cir. 1992) (holding that, where Colo-
rado law creates a presumption that by driving with a speci-
fied blood alcohol content a defendant is driving while
impaired, it is clear that the “driving while ability impaired”
offense is similar to driving under the influence and includ-
able in a defendant’s criminal history score).

   [7] Because we hold that a conviction for violating section
23152(b) is “similar” to a conviction for driving under the
influence, the district court did not need to find that Thorn-
ton’s driving was impaired when he committed the prior
offense in order to include that offense in calculating his crim-
inal history score. Therefore, there was no violation of Thorn-
ton’s Sixth Amendment or due process rights. The district
4254              UNITED STATES v. THORNTON
court made no factual finding that Thornton’s driving was
impaired when he committed his prior offense, and applica-
tion of the Sentencing Guidelines requires no such finding.

   Our holding that a conviction under section 23152(b) is not
a conviction for a minor traffic infraction is also consistent
with United States v. Aichele, 912 F.2d 1170 (9th Cir. 1990).
In Aichele, the defendant challenged the addition of points to
his criminal history score for a prior reckless driving convic-
tion. Aichele argued that he had been convicted of a minor
traffic infraction, which would have been excluded from his
criminal history calculation under section 4A1.2(c). We held:

    We are not left in doubt as to what is an “infraction.”
    An infraction is any offense for which the maximum
    authorized term of imprisonment is not more than 5
    days. 18 U.S.C. § 3559(a). Obviously Aichele’s
    reckless driving conviction was not an infraction,
    much less was it a minor infraction.

Aichele, 912 F.2d at 1171. The maximum authorized term of
imprisonment for a first violation of section 23152(b) is six
months, i.e., more than five days. See Cal. Veh. Code
§ 23536(a). Therefore, under our holding in Aichele, Thorn-
ton’s prior conviction cannot be a minor traffic infraction and
may not be excluded from his criminal history calculation.
Accord United States v. Moore, 968 F.2d 216, 224-25 (2d Cir.
1992) (holding that a New York conviction for “driving while
ability impaired” was properly included in defendant’s crimi-
nal history score because the maximum penalty for the
offense was greater than five days).

   Thornton also argues that a conviction under section
23152(b) is analogous to a conviction for “public intoxica-
tion,” which must be excluded from his criminal history cal-
culation pursuant to U.S.S.G. § 4A1.2(c). Thornton does not
cite to any authority to support his position. We reject this
argument as well.
                 UNITED STATES v. THORNTON               4255
B.   Thornton is not entitled to an Ameline remand.

   The district court sentenced Thornton using the then-
mandatory Sentencing Guidelines. Although Thornton has not
raised an objection under United States v. Booker, 543 U.S.
220 (2005), we may raise and consider the issue of Booker
error sua sponte. United States v. Ameline, 409 F.3d 1073,
1084 (9th Cir. 2005) (en banc) (“Even where the briefs filed
by the parties do not raise a Booker objection, we conclude
that the issue may be raised and should be considered.”); see
United States v. Beck, 418 F.3d 1008, 1016 (9th Cir. 2005);
United States v. Beaudion, 416 F.3d 965, 970 (9th Cir. 2005).

   [8] Although the district court applied the mandatory Sen-
tencing Guidelines to Thornton’s case, if Thornton were
resentenced using the now-advisory Guidelines, the manda-
tory minimum statute requiring him to serve ten years still
would apply. See 21 U.S.C. § 841(b). As explained above,
Thornton does not satisfy the criteria required to invoke sec-
tion 5C1.2’s safety valve provision. This fact remains true
regardless of whether the Guidelines are mandatory or advi-
sory.

   [9] Therefore, Thornton cannot be resentenced to a period
of incarceration of less than 120 months, which is the sen-
tence he currently is serving. Any argument that Thornton
was erroneously sentenced using the mandatory Guidelines is
moot in light of the mandatory minimum sentence. See United
States v. Labrada-Bustamante, 428 F.3d 1252, 1263 (9th Cir.
2005); United States v. Dare, 425 F.3d 634, 643 (9th Cir.
2005). We do not grant an Ameline remand.

                      IV.   Conclusion

   We hold that a conviction under California Vehicle Code
section 23152(b) is a conviction for an offense “similar” to
driving under the influence, and is therefore includable in a
defendant’s criminal history score. See U.S.S.G. § 4A1.2 cmt.
4256              UNITED STATES v. THORNTON
n.5. The district court correctly added one point to Thornton’s
criminal history score for his conviction under section
23152(b). The district court’s calculation of an additional two
criminal history points because Thornton committed the § 846
offense while on probation for his prior crime also was
proper. Because Thornton is subject to a mandatory minimum
sentence of 120 months in prison, any potential Booker error
is moot.

  AFFIRMED.
