dissenting.
This case presents a legal sufficiency claim involving a defense to prosecution. The issues before us are: (1) whether obtaining a controlled substance in a foreign country pursuant to a prescription given by a physician in that country supplies a person with a defense when prosecuted for possessing that controlled substance in Texas, and (2) if such a defense exists, whether the *202evidence is legally sufficient to require application of that defense as a matter of law. The Court of Appeals reversed the conviction and ordered dismissal of the indictment. The majority holds that a defense exists but forecloses a sufficiency review — apparently believing that such review is not appropriate. I would hold that appellant established a defense to prosecution as a matter of law and would remand this cause to the trial court to enter a judgment of acquittal.
I. Statutory defense
The starting point in an analysis of the meaning of a statute is, of course, the language of the statute itself. State v. Hardy, 963 S.W.2d 516, 519 (Tex.Crim.App.1997). We must give effect to the plain meaning of a statute’s words unless the language of the statute is ambiguous or giving effect to the plain meaning would lead to absurd results. Id.; Boykin v. State, 818 S.W.2d 782, 785-786 & 786 n. 4 (Tex.Crim.App.1991). Because the language of the statutes at issue in the present case is unambiguous, I limit my inquiry to the statutory language.
In determining plain meaning of the words in a statute, “[wjords and phrases shall be read in context and construed according to the rules of grammar and usage.” TEX. GOV’T CODE § 311.011(a); Dowthitt v. State, 931 S.W.2d 244, 258 (Tex.Crim.App.1996) In addition, we presume that “the entire statute is intended to be effective.” TEX. GOV’T CODE § 311.021(2); Dowthitt, 931 S.W.2d at 258. Every word in a statute has been used for a purpose and each word, phrase, clause, and sentence should be given effect if reasonably possible. Dowthitt, 931 S.W.2d at 258; Morter v. State, 551 S.W.2d 715, 718 (Tex.Crim.App.1977), quoting Eddins-Walcher Butane Co. v. Calvert, 156 Tex. 587, 591, 298 S.W.2d 93, 96 (1957).
The offense for which appellant was prosecuted provides:
Except as authorized by this chapter, a person commits an offense if the person knowingly or intentionally possesses a controlled substance listed in Penalty Group 3, unless the person obtains the substance directly from or under a valid prescription or order of a practitioner acting in the course of professional practice.
Texas Health & Safety Code § 481.117(a)(emphasis added).1 The “unless” clause of the offense does not apply to the present ease because of the definition of “practitioner” under the statute. “Practitioner” is defined as someone having the authority to practice or distribute medicines in Texas or in another state if the person has a Federal Drug Enforcement Administration registration number. § 481.002(39). Presumably, the physician in Mexico did not fall within those categories.2
Nevertheless, the “Except as authorized by this chapter” phrase clearly indicates that other provisions may establish a defense to prosecution. One such other provision is § 481.062, entitled “Exemptions.” That statute provides in relevant part:
(a) The following persons are not required to register and may possess a controlled substance under this chapter:
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(3) an ultimate user or a person in possession of the controlled substance under a lawful order of a practitioner or in lawful possession of the controlled substance if it is listed in Schedule V;
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§ 481.062(a)(3)(emphasis added). This statutory subsection provides three separate defenses: (1) ultimate user, (2) possession of the controlled substance under a lawful order of a practitioner, and (3) lawful possession of the controlled substance if it is listed in Schedule V. Defenses (2) and (3) are inapplicable to the present case because the Mexican physician was not a “practitioner” and because the substances involved do not fall within Schedule V. See § 481.036 (for listing of Schedule V substances).
*203The question, then, is whether appellant qualifies an “ultimate user” under Texas law. An “ultimate user” is defined as “a person who has lawfully obtained and possesses a controlled substance for the person’s own use, for the use of a member of the person’s household, or for administering to an animal owned by the person or by a member of the person’s household.” § 481.062(48). An initial question is whether the adverb “lawfully” modifies only the verb “obtained” or whether it also modifies the verb “possesses.” “Lawfully” clearly modifies “obtained” because the adverb immediately precedes the verb. But, “lawfully” does not immediately precede “possesses.” For “lawfully” to modify “possesses,” the verb “possesses” must be part of a parallel construction with the verb “obtained.” But, because “lawfully” is imbedded between the helping verb “has” and its object verb “obtained,” there is no parallel construction between “obtained” and “possesses” as they relate to the adverb “lawfully” due to a lack of agreement between the helping verb “has” and the posited object verb “possesses.” An attempt to map a parallel construction of the provision would look like this: “a person who has lawfully obtained and has lawfully possesses a controlled substance for the person’s own use.” Such a parallel construction would be grammatically incorrect. The only proper construction, then, is that “lawfully” modifies “obtained” but does not modify “possesses.”
An evaluation of the language of § 481.062, which provides the defense, leads to the same conclusion. The “ultimate user” defense is contained in the same statutory subsection as another defense containing the phrase “lawful possession.” § 481.062(a)(3). “Lawful possession” has its own definition in the Texas Controlled Substances Act, to wit: “the possession of a controlled substance that has been obtained in accordance with state or federal law.” § 481.002(24). The Legislature could easily have used the already-defined term “lawful possession” in defining “ultimate user” but it did not. And, by pairing the term with one of the other defenses articulated in § 481.062(a)(3), the Legislature further indicated that “lawful possession” was not intended to be a definitional element of the ultimate user defense.
Hence, the ultimate user defense contains two elements: the controlled substance is (1) lawfully obtained and (2) possessed for the person’s own use or for use in that person’s household. The Texas Controlled Substances Act contains no definition of “lawfully obtained.” Undefined words in a statute “are to be understood as ordinary usage allows.” Denton v. State, 911 S.W.2d 388, 390 (Tex.Crim.App.1995). Under ordinary usage, controlled substances obtained in Mexico are lawfully obtained if Mexico’s law so permits. The Court of Appeals and the majority err in concluding that appellant must comply with federal law to establish a defense to prosecution (although she may have in fact complied). So long as appellant properly obtained the substances under the laws of Mexico, those substances are “lawfully obtained” for purposes of the ultimate user defense.
Although neither of the parties have briefed the requirements of Mexico law, we may assume, absent proof to the contrary, that foreign law is the same as the law in the State of Texas. Langston v. State, 776 S.W.2d 586 (Tex.Crim.App.1989). Hence, we can presume that a prescription from a physician licensed in Mexico would authorize obtaining the substances in question in Mexico, just as a prescription from a physician licensed in Texas would authorize obtaining the substances in Texas.
II. Sufficiency
The majority appears to assume that a sufficiency review is inapplicable to defenses; however, such an assumption would be incorrect. We have recognized the legitimacy of mounting a sufficiency of the evidence challenge in the self-defense and statute of limitations contexts. Saxton v. State, 804 S.W.2d 910, 914 (Tex.Crim.App.1991)(self-defense); Proctor v. State, 967 S.W.2d 840 (Tex.Crim.App.1998)(state has the burden to prove limitations once raised by the defense), overruling on other grounds, Lemell v. State, 915 S.W.2d 486(Tex.Crim.App.1995)(discuss-ing sufficiency review and limitations). The Supreme Court has also indicated that defenses may be subject to a sufficiency review. *204See Burks v. United States, 437 U.S. 1, 5-6, 17-18, 98 S.Ct. 2141, 57 L.Ed.2d 1 (1978) (holding that a reversal due to insufficient evidence to negate an insanity defense results in an acquittal for double jeopardy purposes).
In determining the sufficiency of the evidence with respect to a defense, “we determine, whether, after reviewing all the evidence in the light most favorable to the prosecution, any rational trier of fact ... would have found against [the defendant] on the [defensive] issue beyond a reasonable doubt.” Saxton, 804 S.W.2d at 914 (ellipsis added; bracketed material substituted for original). In the present case, both the State (through Frio County Sheriff Burris) and appellant presented evidence that appellant had a prescription from a physician in Mexico for the substances which are the basis of the criminal prosecution. That prescription was stamped “CLEARED U.S. CUSTOMS LAREDO, TEXAS,” and appellant testified that she had in fact presented the prescription and the substances to customs officials for inspection and that they had cleared her to come into the country. Sheriff Burris testified that, when he stopped the ear appellant was riding in, he began inquiring about purchases because he noticed a bag that looked like one that would come from a pharmacy in Mexico. Appellant freely cooperated with Burris’ inquiry and truthfully answered questions about the medications she had purchased. And, Burris acknowledged during testimony that his basis for bringing charges against appellant was that Texas did not recognize foreign prescriptions. Appellant also testified that the medications were for her personal use.
All the evidence in the record, including evidence introduced by the State, shows that the substances in question were legally purchased in Mexico for appellant’s personal use. No evidence in the record casts doubt on the validity of the prescription, nor is there any evidence that suggests that the substances were purchased for something other than appellant’s own personal use.
On petition for discretionary review, the State now claims that there is no evidence in the record, other than the prescription itself, that the doctor from whom appellant obtained the prescription was a fully licensed physician in Mexico. The State further alleges that the prescription negates the inference that the Mexican doctor was a fully licensed physician because no “Dr.” was placed before his name and no “M.D.” was placed after his name. However, the record supports neither of the State’s assertions. Aside from the prescription form, appellant’s testimony supports the proposition that the doctor she saw was a physician. And, the fact that the prescription cleared U.S. customs is also evidence that it was in fact a legitimate prescription. Moreover, the prescription form does contain a “Dr.” before the doctor’s name. The prescription is signed and underneath the signature line is a printed name: “Dr. Joaquin Izaguirre Quintero.” In addition, the prescription form contains the language: “Licencia Sani-taria: 20310,” which appears to be a “health license” and the license number.
The facts establish an ultimate user defense as a matter of law. No rational jury could conclude that appellant was not an ultimate user as defined by the Texas Controlled Substances Act. Appellant is therefore entitled to an acquittal and not merely a new trial. Hence, I would remand this cause to the trial court with instructions to enter a judgment of acquittal. Because the majority does not, I must dissent.
BAIRD, J., joins.
. All further references to sections are to the Texas Health & Safety Code unless otherwise indicated. Any statutory references are to the version in effect at the time of the offense unless otherwise indicated.
. None of the parties suggest otherwise.