IN THE UNITED STATES COURT OF APPEALS
                 FOR THE FIFTH CIRCUIT     United States Court of Appeals
                                                    Fifth Circuit

                                                                      FILED
                                                                 September 22, 2015
                               No. 14-11276
                             Summary Calendar                       Lyle W. Cayce
                                                                         Clerk


UNITED STATES OF AMERICA,

                                          Plaintiff-Appellee

v.

ANTONIO DE JESUS RAMIREZ-OLVERA,

                                          Defendant-Appellant


                Appeals from the United States District Court
                     for the Northern District of Texas


Before WIENER, HIGGINSON, and COSTA, Circuit Judges.
STEPHEN A. HIGGINSON, Circuit Judge:
      Antonio De Jesus Ramirez-Olvera pled guilty to possessing with the
intent to distribute methamphetamine, in violation of 21 U.S.C. § 841(a)(1) and
(b)(1)(B). The district court sentenced him to 240 months—ten years below the
bottom of the applicable guidelines range. He now challenges that sentence,
arguing that the district court erred by not distinguishing between
d-methamphetamine and l-methamphetamine when calculating the quantity
of methamphetamine (actual) attributable to him. We affirm.
      We review de novo the district court’s interpretation of the Sentencing
Guidelines. United States v. Moore, 

, 162 (5th Cir. 2013). “When
the language of the guideline is unambiguous, the plain meaning of that
language is controlling unless it creates an absurd result.” 

Also,
“[t]he Guidelines commentary is authoritative unless it violates the
Constitution or a federal statute, or is inconsistent with, or a plainly erroneous
reading of, that guideline.” 

(citation and internal quotation
marks omitted).
      Ramirez-Olvera's presentence report, prepared by a probation officer,
recommended that, for guideline computations, Ramirez-Olvera should be held
responsible for 7.7 grams of methamphetamine (actual). To reach this figure,
the probation officer relied on the results of DEA laboratory reports that
analyzed the purity of three packages of methamphetamine seized from
Ramirez-Olvera’s house and cars. Ramirez-Olvera objected to the quantity
recommendation on the ground that the laboratory reports did not distinguish
between d-methamphetamine and l-methamphetamine. The district court
overruled the objection.
      Ramirez-Olvera argues that the district court needed to distinguish
between d-methamphetamine and l-methamphetamine when determining the
quantity    of    methamphetamine         (actual)    attributable     to    him.
D-methamphetamine          and   l-methamphetamine     are    “stereoisomers    of
methamphetamine; they consist of identical molecules differently arranged.”
United States v. Acklen, 

, 742 (5th Cir. 1995). Unlike
d-methamphetamine, l-methamphetamine “produces little or no physiological
effect when ingested.” 

internal quotation marks omitted). The
sentencing guidelines provide a base offense level of 38 for an offense involving
4.5 kilograms or more of methamphetamine (actual); they do not explicitly
distinguish between d- and l-methamphetamine. U.S. Sentencing Guidelines
Manual § 2D1.1(c)(1) (2014).
      A 1995 amendment to § 2D1.1 indicates that courts need not distinguish
between d-methamphetamine and l-methamphetamine when determining the
quantity of methamphetamine (actual) attributable to a defendant. That
amendment—Amendment 518—altered the drug equivalency table in § 2D1.1.
Before the amendment, the table distinguished between methamphetamine,
methamphetamine (actual), ice, and l-methamphetamine by assigning each
substance a different marihuana-equivalent. See U.S. Sentencing Guidelines
Manual, § 2D1.1, cmt. n.10 (Nov. 1995). Amendment 518 deleted the table’s
reference to l-methamphetamine. See 

vol. I, amend. 518 (Nov. 1995).
The Sentencing Commission explained the amendment as follows:
      [T]his amendment deletes the distinction between d- and
      l-methamphetamine in the Drug Equivalency Tables in the
      Commentary to § 2D1.1. L-methamphetamine, which is a rather
      weak form of methamphetamine, is rarely seen and is not made
      intentionally, but rather results from a botched attempt to produce
      d-methamphetamine.            Under         this      amendment,
      l-methamphetamine       would be treated the same                as
      d-methamphetamine (i.e., as if an attempt to manufacture or
      distribute    d-methamphetamine).        Currently,   unless    the
      methamphetamine is specifically tested to determine its form,
      litigation can result over whether the methamphetamine is
      l-methamphetamine or d-methamphetamine. . . . Under this
      amendment, all forms of methamphetamine are treated alike,
      thereby simplifying guideline application.

unpublished opinion, we have relied on Amendment 518 to hold that
“any distinction” between d-methamphetamine and l-methamphetamine is
now “immaterial” when calculating drug quantity under the guidelines. United
States v. Beltran, 91 F. App’x 349 (5th Cir. 2004). We conclude that, in light of
Amendment 518, the district court did not need to distinguish between
d-methamphetamine and l-methamphetamine when calculating the quantity
of methamphetamine (actual) attributable to Ramirez-Olvera.
      The judgment of the district court is AFFIRMED.