Reversed and Rendered in Part, Reversed and Remanded in Part, and 

Majority and Dissenting Opinions filed May 28, 2015.

In The

Fourteenth Court of Appeals

NO. 14-13-00706-CR

JOEL NAVARRO, Appellant

V.

THE STATE OF TEXAS, Appellee

On Appeal from the County Criminal Court at Law No. 15

Harris County, Texas

Trial Court Cause No. 1836127

M A J O R I T Y O P I N I O N

This is an appeal from a Class A misdemeanor conviction for driving while 

intoxicated. At the trial court level, the State argued that a finding of intoxication 

under the per se theory of intoxication could be based on the alcohol content of 

appellant’s blood plasma rather than his whole blood. Now the State confesses 

error on that point. 
2

At the trial court level, the trial judge failed to submit a question to the jury 

as to whether appellant’s blood alcohol level was at least 0.15 to support the Class 

A misdemeanor conviction. Now the State confesses error on that point.

At the trial court level, the State convinced the trial judge that a Class A 

misdemeanor conviction could be based on blood plasma results, and the trial 

judge made a finding that appellant had an alcohol concentration of at least 0.15. 

Now the State confesses error on that point.

Despite misleading both the trial judge and the jury, through both an 

improper charge and an improper closing argument, the State argues that appellant 

is not entitled to a new trial. The State believes that the judgment should be

reformed to reflect a conviction for a Class B misdemeanor, and the case should be 

remanded for a new punishment hearing only. We disagree. We reverse and render 

a judgment of acquittal on the Class A misdemeanor, and we remand for a new 

trial on the Class B misdemeanor.

BACKGROUND

Appellant and his fiancée were involved in a single-vehicle accident, the 

cause of which was disputed at trial. Only one eyewitness testified at trial. The 

eyewitness testified that he was driving down the interstate late at night when a 

truck in front of him suddenly veered to the left and struck a concrete barrier. 

Traffic had been light at the time, it had not been raining, and there was no 

evidence of an obstruction in the road that would have required an evasive 

maneuver.

The truck rolled over three times and landed upright on its tires. When the 

eyewitness pulled up next to the truck, he saw appellant climbing out of the 

driver’s side window, apparently because the door had been jammed. Appellant 
3

crawled on the pavement towards his fiancée, who had been ejected from the truck 

during the rollover. She was unconscious, severely injured, and lying about thirtyfive feet away from where the truck had finally stopped.

Appellant told first responders that he was driving at the time of the 

accident. He explained that he and his fiancée were arguing inside the truck, that 

she grabbed the steering wheel at one point, and that he overcorrected. This story 

gradually changed over time. Appellant later claimed that his fiancée was feeling 

sick, that she slid over to be next to him, and that she accidentally hit the steering 

wheel. At another point, appellant reported that the accident happened because a 

tire blew out.

The police did not initially suspect that the accident was alcohol-related. In 

fact, the officer who questioned appellant at the scene opined in his original police 

report that appellant was not intoxicated.

There was evidence of intoxication, however. According to an emergency 

medical technician, appellant admitted that he had consumed at least four beers on 

the night of the accident. There was also blood evidence taken more than an hour

after the accident, and the evidence indicated that appellant had alcohol in his 

system.

The blood evidence was obtained at the hospital where appellant and his 

fiancée were treated. The hospital collected a vial of appellant’s whole blood, 

which was then placed into a centrifuge. The vial was spun, causing the blood cells 

to separate from the blood plasma. A test of the blood plasma revealed that 

appellant had a blood-alcohol concentration (“BAC”) of 0.158.1

 

1

In this opinion, all numerical references to BAC are expressed in the same units: grams 

of alcohol per 100 milliliters of blood. We denote in each instance whether the blood at issue is 

whole blood or blood plasma.
4

Charges were eventually brought against appellant for driving while 

intoxicated. The charging instrument included an additional allegation that, at or 

near the time of the commission of the offense, appellant’s blood showed “an 

alcohol concentration level of at least 0.15.”

The State’s expert, William Arnold of the Houston Police Department,

testified that the concentration of alcohol is higher in blood plasma than it is in 

whole blood. The expert opined that a BAC of 0.158 in blood plasma could be 

converted to a BAC of 0.132 in whole blood. Assuming that appellant had been

eliminating alcohol from his system, instead of absorbing it, the expert believed

that appellant had a BAC of 0.133 in whole blood at the time of the accident.

Appellant did not testify at trial, but he asserted several defensive theories, 

one of which was that his fiancée had been driving when the accident occurred.

Appellant argued that his statements to first responders had been false, and that he 

had only taken the blame for the accident because he felt a duty to protect his 

fiancée.

There was affirmative evidence to support this theory. The record showed

that appellant was excluded as a contributor of a DNA sample collected from the 

driver’s side air bag. The DNA revealed a partial profile belonging to a female of 

unknown origin, who could have been the fiancée.

Other evidence included testimony from the fiancée herself, who recovered 

from her injuries after being in a coma for nearly a month. The fiancée admitted 

that she did not remember much from the accident, but she testified that there was 

“a good chance” that she was the driver. The fiancée explained that the truck 

belonged to her, not appellant. She was possessive over the truck, and only allowed 

appellant to drive it on rare occasions. She also observed photographs of the truck 

after the accident, and said that the position of the driver’s seat would have been 
5

uncomfortable for appellant, who is more than a foot taller than she is and has a 

much larger frame.

The trial court instructed the jury that it could make a finding of intoxication 

in either of two ways: (1) if appellant did not have the normal use of his mental or 

physical faculties by reason of the introduction of alcohol into his body, or (2) if 

appellant had an alcohol concentration of 0.08 or more. “Alcohol concentration” 

was defined in the court’s charge as “the number of grams of alcohol per 100 

milliliters of blood.” Appellant objected to this definition because it did not specify

that the blood must be whole blood. Appellant requested that the definition be 

revised to read as follows: “the number of grams of alcohol per 100 milliliters of 

whole blood.” The trial court denied the request.

During closing arguments, the issue over blood evidence arose again when 

the prosecutor advised the jury that it was not limited by the type of blood that it 

could consider. The prosecutor said:

As you know, we have heard a lot of evidence today and we heard a 

lot about blood evidence today. I just want to draw y’all’s attention to 

the charge, that you will be given the definition of what an alcohol 

concentration is and that definition is the number of grams of alcohol 

per 100 milliliters of blood. You won’t find anywhere in here in the 

law where it needs to be whole blood or plasma blood. This is the law 

y’all follow.

Appellant objected to this argument as a misstatement of law. He explained,

“The law requires whole blood.” But the trial court overruled the objection. The 

prosecutor later expanded on her argument, saying directly and without objection 

that the jury could find that appellant was intoxicated based solely on the testing of 

his blood plasma.

The jury convicted appellant of driving while intoxicated, but it did not 

make the additional finding that he had “an alcohol concentration level of at least 
6

0.15,” as had been alleged in the charging instrument. The trial court did not 

submit that issue in the jury charge.

Appellant elected to have the trial court assess his punishment. No new 

evidence was offered during this phase. The trial court began the hearing by 

treating the additional allegation in the charging instrument as an enhancement 

paragraph, which the court found to be true. By making an affirmative finding that 

appellant had “an alcohol concentration level of at least 0.15,” the court applied a 

range of punishment applicable to a Class A misdemeanor, instead of a Class B 

misdemeanor, which is what appellant would have faced without the perceived 

“enhancement.”

SUFFICIENCY OF THE EVIDENCE

I. The Jury’s Finding

Appellant was charged under section 49.04(a) of the Texas Penal Code, 

which provides: “A person commits an offense if the person is intoxicated while 

operating a motor vehicle in a public place.” In his first issue, appellant contends 

that the evidence is legally insufficient to show either (1) that he was the driver of 

the truck, or (2) that he was intoxicated.

When reviewing the legal sufficiency of the evidence, we examine all of the 

evidence in the light most favorable to the verdict and determine whether a rational 

trier of fact could have found the essential elements of the offense beyond a 

reasonable doubt. See Temple v. State, 390 S.W.3d 341, 360 (Tex. Crim. App. 

2013). The evidence is insufficient when the record contains no evidence, or 

merely a “modicum” of evidence, probative of an element of the offense. See 

Garcia v. State, 367 S.W.3d 683, 687 (Tex. Crim. App. 2012).
7

Although we consider everything presented at trial, we do not reevaluate the 

weight and credibility of the evidence or substitute our judgment for that of the fact 

finder. See Williams v. State, 235 S.W.3d 742, 750 (Tex. Crim. App. 2007). 

Because the jury is the sole judge of the credibility of witnesses and of the weight 

given to their testimony, any conflicts or inconsistencies in the evidence are 

resolved in favor of the verdict. See Wesbrook v. State, 29 S.W.3d 103, 111 (Tex. 

Crim. App. 2000). Our review includes both properly and improperly admitted 

evidence. See Clayton v. State, 235 S.W.3d 772, 778 (Tex. Crim. App. 2007). We 

also consider both direct and circumstantial evidence, as well as any reasonable 

inferences that may be drawn from the evidence. Id. Circumstantial evidence is as 

probative as direct evidence in establishing the guilt of an actor, and circumstantial 

evidence alone can be sufficient to establish guilt. See Hooper v. State, 214 S.W.3d 

9, 13 (Tex. Crim. App. 2007).

A. Driver

Appellant acknowledges that he initially admitted to first responders that he 

was driving the truck at the time of the accident. He suggests, however, that his

admissions must be disregarded because he was actually lying to protect his 

fiancée. 

We do not agree that the admissions must be disregarded. The jury was free 

to believe appellant’s original statements, and under the applicable standard of 

review, those statements must be credited because they support the jury’s verdict.

See Guess v. State, 419 S.W.3d 361, 366 (Tex. App.—Tyler 2010, pet. ref’d) 

(holding that the jury was entitled to believe the defendant’s initial statement to 

police that he was the one who drove off the road).

Appellant’s admissions are also corroborated by other evidence. For 

instance, blood was found on the driver’s side headrest, but unlike the sample that 
8

was collected from the driver’s side air bag, DNA testing revealed that a male of 

unknown origin had contributed the blood. Because appellant was the only male in 

the vehicle, the jury could have reasonably believed that appellant was the 

contributor, and that the blood transferred to the headrest because appellant had 

been sitting in the driver’s seat.

Additionally, an eyewitness testified that he saw appellant climbing out of 

the driver’s side window immediately after the accident. For the same reason as 

before, the jury could have inferred that appellant was exiting from that side 

because he had previously been driving. Cf. Dickson v. State, 642 S.W.2d 185, 189 

(Tex. App.—Houston [14th Dist.] 1982, pet. ref’d) (evidence supported a finding 

that the defendant had been driving a vehicle when the defendant was seen 

emerging from the driver’s side immediately after the vehicle was stopped).

We do not doubt that the jury could have made the opposite finding that 

appellant was merely a passenger at the time of the accident. Appellant certainly 

produced evidence that created a fact issue on this point. But in such 

circumstances, it is not the role of this court to determine which evidence the jury 

should have believed. See Wicker v. State, 667 S.W.2d 137, 143 (Tex. Crim. App. 

1984). Viewing the evidence in the light most favorable to the jury’s verdict, we 

conclude that a rational finder of fact could have determined beyond a reasonable 

doubt that appellant was driving the truck at the time of the accident.

B. Intoxicated

The jury received the statutory definition of “intoxicated,” which has two 

alternative meanings: “(A) not having the normal use of mental or physical 

faculties by reason of the introduction of alcohol . . . into the body; or (B) having 

an alcohol concentration of 0.08 or more.” See Tex. Penal Code § 49.01(2). We 

have described these meanings as providing alternative methods of proving that a 
9

person is intoxicated. See Bradford v. State, 230 S.W.3d 719, 721–22 (Tex. App.—

Houston [14th Dist.] 2007, no pet.). The two methods are known, respectively, as 

the impairment theory of intoxication and the per se theory of intoxication. Id. 

Because the two methods of proof are not mutually exclusive, evidence offered 

under the per se theory can also support a finding that a person is impaired. See 

Crenshaw v. State, 378 S.W.3d 460, 467 (Tex. Crim. App. 2012). As indicated 

above, proof under the per se theory requires an alcohol concentration expressed in 

grams of alcohol per 100 milliliters of blood. See Tex. Penal Code § 49.01(1)(B).

Appellant contends that the evidence is insufficient to show that he was 

intoxicated, citing multiple reasons. He points out first that an investigating officer 

originally reported that appellant was not intoxicated. Along this same track, 

appellant refers to testimony that field sobriety tests were never administered on 

him, that he was never found to have been slurring his words, and that he was 

actually found to be alert and oriented immediately after the accident.

On a different track, appellant asserts that the blood evidence failed to meet 

certain standards. Appellant complains that the expert who calculated the BAC of 

his whole blood used a conversion ratio based on a scientific average, rather than a 

consideration of appellant’s individual characteristics. Appellant points out that 

conversions depend heavily on the health of the person, and if his health were 

shown to be outside the average, then a certain conversion would have established 

that he was not intoxicated.

The expert’s testimony was primarily used to prove that appellant was 

intoxicated under the per se theory. Even if we were to conclude that the expert’s 

methodology was inexact, the conviction would still be supported if there were

legally sufficient evidence offered under the impairment theory. We conclude that 

the record contains such evidence.
10

The jury heard that appellant admitted to having consumed at least four 

beers on the night of the accident. Thus, there is some proof that alcohol was 

introduced into appellant’s body. The jury could have reasonably determined that 

the accident occurred because appellant lost the normal use of his faculties by 

reason of that introduction.

The absence of certain environmental factors supports that implied finding. 

The record shows that there were few cars on the road, and that it had not been 

raining. There is also no evidence of an obstacle in the road that would have 

required a sudden turn.

There was some testimony that the accident could have occurred for reasons 

other than intoxication: appellant may have overcorrected, his fiancée may have 

accidentally hit the steering wheel, or a tire may have blown out. But the jury was 

free to disbelieve this evidence and conclude that appellant was impaired by his 

consumption of alcohol. We conclude that there is legally sufficient evidence of 

appellant’s intoxication, and that a rational jury could have found every element of 

the offense beyond a reasonable doubt. See Lorenz v. State, 176 S.W.3d 492, 495 

(Tex. App.—Houston [1st Dist.] 2004, pet. ref’d) (concluding that the evidence 

was sufficient to prove the defendant’s intoxication when, among other factors, 

there was evidence that the defendant admitted to having consumed portions of 

three alcoholic beverages).

II. The Trial Court’s Finding

In its brief, the State makes a “Confession of Unassigned Error,” contending 

that there is legally insufficient evidence to support the trial court’s finding that 

appellant had “an alcohol concentration level of at least 0.15.” The State bases this

confession on authority that the statutory meaning of “blood” is restricted to whole 

blood, as appellant argued at trial, and there is no evidence that the BAC of 
11

appellant’s whole blood was at least 0.15. Even if there were legally sufficient 

evidence, the State asserts that the trial court should not have made its finding 

because appellant’s alcohol concentration level was an element of an offense, and 

therefore, it should have been submitted to the jury during the guilt-innocence

phase of trial.

Appellant did not respond to the State’s confession in his reply brief, but we 

may still address an unassigned error if it was preserved below. See Sanchez v. 

State, 209 S.W.3d 117, 120–21 (Tex. Crim. App. 2006). Because a defendant need 

not preserve error as to a claim that the evidence is insufficient to prove an element 

of the offense for which he was convicted, we choose to address this issue. See 

Flanary v. State, 166 Tex. Crim. 495, 496, 316 S.W.2d 897, 898 (1958) (op. on 

reh’g).

A. Element or Enhancement?

We must first decide whether a person’s alcohol concentration level 

provides a basis for enhancement, as the trial court believed, or whether it 

functions as the element of a completely separate offense, as the State asserts on 

appeal.

In Calton v. State, the Court of Criminal Appeals explained the differences 

between elements and enhancements. See 176 S.W.3d 231 (Tex. Crim. App. 2005). 

The court said that the elements of an offense are defined as “the forbidden 

conduct, the required culpability, any required result, and the negation of any 

exception to the offense.” Id. at 233. A reviewing court must look to the plain 

language of the statute when discerning whether any given fact constitutes an 

element of the offense. Id.
12

An enhancement, by contrast, is a fact that increases the punishment range to 

a certain range above what is ordinarily prescribed for the crime that was charged. 

Id. “It does not change the offense, or the degree of the offense, of conviction.” Id.

With those considerations in mind, we now turn to the relevant statute, the 

full text of which provides as follows: 

(a) A person commits an offense if the person is intoxicated 

while operating a motor vehicle in a public place.

(b) Except as provided by Subsections (c) and (d) and Section 

49.09, an offense under this section is a Class B misdemeanor, with a 

minimum term of confinement of 72 hours.

(c) If it is shown on the trial of an offense under this section 

that at the time of the offense the person operating the motor vehicle 

had an open container of alcohol in the person’s immediate 

possession, the offense is a Class B misdemeanor, with a minimum 

term of confinement of six days.

(d) If it is shown on the trial of an offense under this section 

that an analysis of a specimen of the person’s blood, breath, or urine 

showed an alcohol concentration level of 0.15 or more at the time the 

analysis was performed, the offense is a Class A misdemeanor.

Tex. Penal Code § 49.04.

There is only a single reference in this statute to “an alcohol concentration 

level,” and it is located under Subsection (d). A plain reading of that subsection 

reveals that its effect is to convert an offense from a Class B misdemeanor to a 

Class A misdemeanor whenever a person charged with driving while intoxicated is 

shown to have “an alcohol concentration level of 0.15 or more.” Because this 

conversion represents a change in the degree of the offense, rather than just an 

enlargement of the punishment range for a Class B misdemeanor, we agree with 

the State that a person’s alcohol concentration level is not a basis for enhancement. 

See Calton, 176 S.W.3d at 233 (an enhancement does not change the degree of the 
13

offense of conviction). It is instead an element of a separate offense because it 

represents a specific type of forbidden conduct—operating a motor vehicle while 

having an especially high concentration of alcohol in the body. Cf. Mapes v. State, 

187 S.W.3d 655, 658 (Tex. App.—Houston [14th Dist.] 2006, pet. ref’d) (stating 

that in a prosecution under Section 49.09, where the defendant is accused of 

driving while intoxicated and of having prior convictions for driving while 

intoxicated, the prior convictions are elements of the offense, and not bases for 

enhancement, in part because they affect the degree of the offense).

B. Meaning of “Blood” and Evidence of Alcohol Concentration

The evidence shows that a vial of appellant’s whole blood was obtained at 

the hospital more than an hour after the accident occurred. From that sample, the 

blood plasma was separated from the blood cells, and testing of the blood plasma 

revealed that appellant had a BAC of 0.158. This was the only blood sample that 

was ever tested for its alcohol content.

The State’s expert converted the blood plasma results using a scientifically 

accepted method and concluded that appellant’s whole blood had a BAC of 0.132. 

There was no testimony that appellant’s whole blood had a BAC that was 0.15 or 

more at the time the analysis was performed.

2

Based on this evidence, a finding that appellant had “an alcohol 

concentration level of 0.15 or more” could be supported only if a person’s alcohol 

concentration was measured in units of blood plasma, and not whole blood.

3

The 

 

2 We explain, infra, at note 6, that the expert’s calculations were wrong. However, even if 

the expert had correctly converted the results of appellant’s blood plasma testing, there would 

still be no showing that the BAC of appellant’s whole blood was at least 0.15 at the time the 

analysis was performed.

3 Although alcohol concentration is a separate element of the Class A misdemeanor 

offense, appellant has not argued that the trial court violated his due process rights by not 

submitting that element to the jury. Cf. Ex parte Boyd, 58 S.W.3d 134, 136 (Tex. Crim. App. 
14

statute defining “alcohol concentration” does not provide express guidance on this 

point. It does not say, for instance, whether proof must be submitted in units of 

whole blood or blood plasma. Rather, it generally provides that alcohol 

concentration means the number of grams of alcohol per 100 milliliters of “blood,” 

without specifying which type. See Tex. Penal Code § 49.01(1)(B).

The word “blood” is not defined in the Penal Code, but the Court of 

Criminal Appeals has indicated that it can only mean whole blood. In Bigon v. 

State, the court discussed the reliability of certain methods for converting the BAC 

of blood serum into the BAC of whole blood. See 252 S.W.3d 360, 368 (Tex. 

Crim. App. 2008). If our criminal statutes did not require proof of a person’s 

intoxication as expressed in units of whole blood, there would have been no need 

for the conversion testimony. Therefore, Bigon supports the conclusion that 

“blood” means “whole blood.”

The common definition of “blood” enforces the conclusion that the word 

encompasses more than just blood plasma. A leading dictionary describes blood as 

“the usually red fluid, consisting of plasma, red and white blood cells, etc., that 

circulates through the heart, arteries, and veins of vertebrates.” See Webster’s New 

World College Dictionary 150 (3d ed. 1996). Medical texts contain similar 

definitions. See Gray’s Anatomy [5] (15th ed. 1995) (“Blood consists of a faintly 

yellow fluid, the plasma or liquor sanguinis, in which are suspended numerous 

minute particles, the blood corpuscles, the majority of which are coloured and give 

to the blood its red tint.”).

 

2001) (applying Apprendi v. New Jersey, 530 U.S. 466, 490 (2000)). In any event, we need not 

address this issue because we conclude that appellant is entitled to an acquittal of the Class A 

misdemeanor on other grounds.
15

The Legislature has also signaled its intent that blood should not be 

synonymous with blood plasma. In another statute proscribing the sale of human 

organs, the Legislature expressly provided that the term “human organ” does not 

include “hair or blood, blood components (including plasma), blood derivatives, or 

blood reagents.” See Tex. Penal Code § 48.02(a). Because the Legislature 

described plasma as a “blood component,” and juxtaposed that term with “blood” 

itself, we must conclude that plasma is a only subset of blood, and that the two 

terms are not congruent.

If we apply that same understanding to the chapter proscribing the offense of 

driving while intoxicated, then “blood” as used in the definition of “alcohol 

concentration” must not mean “blood plasma” or any other “component” of blood. 

See Tex. Gov’t Code § 311.011(b) (providing that words that have acquired a 

technical or particular meaning, whether by legislative definition or otherwise, 

should be construed accordingly). Instead, it must mean blood with all of its 

components, which is otherwise known as “whole blood.”

Because there is indeed no evidence that the BAC of appellant’s whole 

blood was ever 0.15 or greater at the time of the blood draw, we agree with the 

State’s confession of error that the trial court’s finding is unsupported by the 

record. If that were the only issue in the case, we would reform the trial court’s 

judgment to reflect a conviction for a Class B misdemeanor, which is supported by 

sufficient evidence as explained above, and remand for a new punishment hearing.

See Calton, 176 S.W.3d at 233; Bowen v. State, 374 S.W.3d 427, 432 (Tex. Crim. 

App. 2012). Appellant has asserted other issues, however, and as we explain 

below, those issues require a new trial.
16

CHARGE INSTRUCTION

In his second issue, appellant contends that the trial court committed charge 

error when it denied a request to clarify the definition of “alcohol concentration” so 

that it was expressed in terms of “whole blood,” rather than just “blood.” We 

review this complaint under a two-step process, considering first whether error 

exists. See Ngo v. State, 175 S.W.3d 738, 743 (Tex. Crim. App. 2005). If error 

does exist, we then analyze that error for harm under the procedural framework of 

Almanza v. State, 686 S.W.2d 157 (Tex. Crim. App. 1984).

I. Error

The trial court must give the jury “a written charge distinctly setting forth 

the law applicable to the case.” See Tex. Code Crim. Proc. art. 36.14. The State 

contends that the trial court fulfilled this duty because its charge gave a definition 

of “alcohol concentration” that exactly tracked the language of Section 49.01. The 

charge provided: “‘Alcohol concentration’ means the number of grams of alcohol 

per 100 milliliters of blood.”

The Court of Criminal Appeals has previously stated that a jury charge that 

tracks the language of a statute is “a proper charge on the statutory issue.” See 

Riddle v. State, 888 S.W.2d 1, 8 (Tex. Crim. App. 1994). This rule has been

expressed in other settings as well, but the court has not always adhered to it. For 

instance, when the issue is whether an indictment should be quashed for failing to 

provide adequate notice, the court has held that tracking the language of the statute 

may not always be sufficient. In Haecker v. State, the court explained that a 

charging instrument does not provide adequate notice if it tracks the language of 

the statute and the statute itself is not “completely descriptive of the offense.” See 

571 S.W.2d 920, 921 (Tex. Crim. App. [Panel Op.] 1978). Similarly, in State v. 

Mays, the court held that an indictment will require greater specificity when a 
17

statute uses “an undefined term of indeterminate or variable meaning.” See 967 

S.W.2d 404, 407 (Tex. Crim. App. 1998).

The principles behind Haecker and Mays guide us when reviewing the 

correctness of a jury charge. As the Court of Criminal Appeals recently reiterated, 

“It is not the function of the charge merely to avoid misleading or confusing the 

jury: it is the function of the charge to lead and to prevent confusion.” Reeves v. 

State, 420 S.W.3d 812, 818 (Tex. Crim. App. 2013) (quoting Williams v. State, 547 

S.W.2d 18, 20 (Tex. Crim. App. 1977)) (emphasis added). A charge will not 

prevent confusion if the statutory text on which it is based has a variable meaning 

in the eyes of the jury.

Standing alone, the statute here is not ambiguous or confusing. “Blood,” as 

that term is used in Section 49.01, can have only one meaning, and that meaning is 

“whole blood” as explained above. But during the trial, the jury was not advised of 

this specific definition, and even before closing arguments began, the jury received 

conflicting messages regarding its meaning.

When the State’s expert took the stand, appellant cross-examined him about 

the proof needed to establish that a person is legally intoxicated. The jury heard the 

following testimony:

Q. And in terms of the law and forensics, Texas requires that the 

sample be whole blood, correct?

STATE: Objection, Your Honor, that’s not the law.

COURT: Overruled.

A. Not that I’m aware.

Q. Let me rephrase. Not that the—it doesn’t require that the 

sample itself be whole blood, but the law mandates that the 

levels of alcohol be related to whole blood, correct?
18

STATE: Objection, Your Honor, calls for a legal 

conclusion.

COURT: Overruled.

A. It dictates units. Off the top of my head, I’m afraid I can’t 

answer regarding the exact statement in the law.

Q. Okay. You’re familiar with the term “BAC”?

A. Yes.

Q. And what does that stand for?

A. BAC can be used—typically it’s used for blood alcohol 

concentration.

Q. Okay. And if I said to you in Texas the law is that you can’t 

have .08, I believe it’s milligrams?

A. It would be grams per one hundred milliliters.

Q. Okay. So, of whole blood, correct?

A. Again, I would have to go back and look. It’s .08 grams per 100 

milliliters is what I remember, at this point.

Q. So, you’re not even aware whether the law in Texas requires 

whole blood or plasma blood?

A. Without—we report all values as blood alcohol whole blood 

equivalent. I know we do run serum and plasma and then 

convert them to the whole blood equivalent and that is standard 

practice throughout the United States. I’m not going to go off 

and venture out to say what Texas law specifically delineates in 

their statutes.

The jury never received a definitive answer from the expert, and the State 

obfuscated the issue by objecting to any suggestion that whole blood is the sole 

unit of measurement under the statute. As discussed further below, the State also 

suggested to the jury in its closing argument that whole blood did not need to be 

the unit of measurement, and the trial court overruled appellant’s objection to this 

argument.
19

This is not a case where the jury was free to assign its own understanding to 

an undefined term from a statute. Cf. Kirsch v. State, 357 S.W.3d 645, 652 (Tex. 

Crim. App. 2012) (holding that the jury should have been free to decide on its own 

whether the evidence showed that the defendant was “operating” a motor vehicle). 

The word “blood” is capable of only one meaning under the Penal Code, and the 

jury should have been instructed of that meaning because it was the law applicable 

to the case. Because the jury heard testimony regarding both whole blood and 

blood plasma, we conclude that it was error to refuse appellant’s requested 

instruction, which removed the possibility of confusion by specifying the type of 

blood evidence that was available for consideration.

II. Harm

Under Almanza, the level of harm necessary for reversal depends on whether 

the defendant timely and specifically objected to the jury charge. See Almanza, 686 

S.W.2d at 171. If the defendant did not object, then reversal is required only if the 

trial court’s error was so egregious and created such harm that the defendant did 

not have a fair and impartial trial. Id. Because the defendant in this case properly 

objected, reversal is required if there was just “some harm.” Id.

To determine harm, we weigh the following factors: (1) the jury charge as a 

whole; (2) the arguments of counsel; (3) the entirety of the evidence; and (4) any 

other relevant factors present in the record. See Warner v. State, 245 S.W.3d 458, 

461 (Tex. Crim. App. 2008). Even though the “some harm” standard is a low 

threshold, it nonetheless requires the reviewing court to find actual harm, rather 

than just theoretical harm. Id. Neither party bears the burden on appeal to prove 

harm or harmlessness. Id. at 462.
20

A. The Jury Charge

The jury received a single instruction, which asked it to determine whether 

appellant had “unlawfully operate[d] a motor vehicle in a public place while 

intoxicated.” As stated above, the definition of “intoxicated” tracked the language 

of Section 49.01, meaning that the jury was allowed to convict appellant on either 

the impairment theory of intoxication or the per se theory of intoxication.

However, the jury was never asked to identify which theory it used in the event of 

a conviction. Thus, we cannot know whether the jury found that appellant had lost 

the normal use of his faculties as the result of his consumption of alcohol, whether 

it found that the alcohol concentration in his blood was above the legal limit under 

the legally flawed portion of the charge, or whether it made findings under both 

theories. Accordingly, we turn to the other factors to determine whether the 

erroneous denial of appellant’s requested instruction might have prejudiced the 

jury’s consideration of the evidence or substantially affected their deliberations.

See Bagheri v. State, 119 S.W.3d 755, 763 (Tex. Crim. App. 2003).

B. Closing Arguments

Appellant’s main defensive theory was that he was not the driver. During 

closing arguments, appellant spent most of his time explaining that his fiancée was 

responsible for the accident, and that he had initially taken the blame because he 

wanted to protect her.

In the alternative, appellant also argued that he was not intoxicated, a point 

that would have been relevant only in the event that he was found to be driving. 

Appellant limited his argument to just the impairment theory of intoxication. He 

asked the jury to acquit him because testimony from the first responders supported 

a finding that he was not impaired.
21

The State argued that appellant was the driver and that he should be found 

guilty under either theory of intoxication. As for the impairment theory, the State 

recited testimony that appellant had consumed several beers on the night of the 

accident. As for the per se theory, the State pointed to the expert’s opinion

regarding the alcohol concentration in appellant’s whole blood and blood plasma.

Appellant asserts in his third issue that the State made an improper closing 

argument. We will consider this issue as part of our harm analysis for charge error.

At the beginning of its closing argument, the State told the jury: “You won’t find 

anywhere in here in the law [the charge] where it needs to be whole blood or 

plasma blood. This is the law y’all follow.” Appellant objected to this argument 

and asserted that the “law requires whole blood,” but the trial court overruled the 

objection. By overruling appellant’s objection, the trial court gave the incorrect 

impression that a conviction could be had by evidence other than whole blood, 

thereby magnifying the possibility for harm. See Good v. State, 723 S.W.2d 734, 

738 (Tex. Crim. App. 1986); Kincaid v. State, 534 S.W.2d 340, 342 (Tex. Crim. 

App. 1976). Later, the State further magnified this erroneous ruling by telling the 

jury that it could convict appellant because the BAC of his blood plasma exceeded

0.15.

The State’s argument was a misstatement of law.

4

Proof under the per se 

theory must be based on evidence of a person’s BAC in whole blood. The trial 

 

4

The State contends that its trial argument was “plainly true” and an accurate description 

of the jury charge. Because the charge did not specify that appellant’s alcohol concentration must 

be measured in units of whole blood, the State believes it could not be improper to say that the 

charge was silent. We disagree. By emphasizing that the charge was silent, the State’s manifest 

objective was to convey to the jury that it could base a finding of intoxication on either the 

evidence of whole blood or the evidence of blood plasma. This effect made the argument 

improper, even though it was otherwise grounded by an accurate statement of fact. Cf. Myers v. 

State, 573 S.W.2d 19, 20–21 (Tex. Crim. App. [Panel Op.] 1978) (prosecutor made an improper 

closing argument when a comment about an accurate statement of fact created an implied or 

indirect allusion to the defendant’s failure to testify).
22

court put its imprimatur on the improper argument by overruling an objection that 

“the law requires whole blood.” Had the trial court granted appellant’s requested 

instruction, the State would have known not to make its improper argument, and 

the jury never would have heard those prejudicial remarks.

C. The Evidence

Appellant presented affirmative evidence in support of two defensive 

theories: (1) that he was not the driver, and (2) that he was not intoxicated. The 

jury rejected the evidence as it related to the first defensive theory. The jury found 

that appellant was the driver, and we have no reason to suspect that this finding 

was a byproduct of the trial court’s charge error. If the error had any impact at all 

on the jury’s deliberations, it affected the manner in which the jury assessed the 

evidence of appellant’s intoxication.

Insofar as the impairment theory of intoxication is concerned, the evidence 

was conflicting. The State produced evidence that appellant was impaired: he 

admitted that he consumed several beers, he had alcohol in his system, and there 

was no environmental cause for explaining the accident. Appellant emphasized a 

different view of the evidence: the first responders believed that he was not 

intoxicated, he was not slurring his speech, and he was described as being alert and 

oriented. There was also evidence suggesting that the accident could have resulted 

from a cause other than intoxication, such as an overcorrection. This alternative 

explanation created a fact question for the jury to resolve.

As for the per se theory, the evidence was complex. A hospital technician 

testified that appellant’s blood sample was obtained solely for purposes of 

treatment, not forensics. The technician recognized that there were differences

between whole blood and blood plasma, but he could not explain how the 
23

concentrations of alcohol varied between the two samples. The only witness who 

could explain that relationship was the State’s expert, William Arnold.

The expert testified that the BAC of a person’s blood “serum” is 16% higher 

than the BAC of his whole blood.5 Applying that ratio to the BAC of appellant’s 

blood plasma, the expert opined that appellant’s whole blood had a BAC of 0.132 

at the time of the blood draw.6

During a voir dire examination, the expert conceded that his 16% ratio was 

not universally accepted throughout the scientific community. He explained that 

16% is just an average, and that the range of ratios can be “quite dramatic” 

depending on the health and gender of the person. If a person has a high blood cell 

count—for example, if he has leukemia—then the BAC of the person’s blood 

plasma can be 50% or 60% higher than the BAC of his whole blood.

The expert testified that he had “no idea” what ratio should apply in 

appellant’s case. The expert never considered appellant’s individual characteristics, 

and there was no live testimony establishing whether appellant had a blood cell 

count that was within normal ranges.7The expert advised the jury, however, that if 

 

5

The expert did not provide a ratio as it specifically relates to a person’s blood “plasma,” 

but we recognize that the differences between blood serum and blood plasma are small. Studies 

have shown that alcohol concentrations are often very close between the two samples, if not the 

same, with an average variance of approximately 1%. See Charles L. Winek & Mark Carfagna, 

Comparison of Plasma, Serum, and Whole Blood Ethanol Concentrations, 11 J. Analytical 

Toxicology 267, 267–68 (1987) (cited approvingly in Bigon, 252 S.W.3d at 368 n.6). 

6

It appears that the expert miscalculated here. He subtracted 16% of 0.158 from 0.158 

(which is the same as multiplying 0.158 by 0.84), when he should have divided 0.158 by 1.16. 

See Jessup v. State, No. 13-02-00024-CR, 2004 WL 2612958, at *3 (Tex. App.—Corpus Christi 

Nov. 10, 2004) (mem. op., not designated for publication) (reciting expert testimony that the 

BAC of whole blood is derived by “divid[ing] the serum concentration by 1.16”). The difference 

between the expert’s miscalculation and the correct calculation is de minimis.

7 Our dissenting colleague points out that appellant’s hematologic history was checked as 

normal, according to a report attached to his medical records. However, this report was never 

discussed at trial, and there is no indication that the jury ever saw it. At the end of closing 
24

a higher conversion ratio did apply to appellant because he had a high blood cell 

count, then the BAC of his whole blood would have been 0.079, below the per se 

limit.

In addition to this conversion testimony, the expert provided a retrograde 

extrapolation analysis. The expert explained that when a person consumes alcohol, 

his body will absorb the alcohol into his system until it is eliminated by the liver. 

During the absorption phase, the concentration of alcohol in the body will increase

at a rate that depends on a number of factors, such as how many drinks were 

consumed, how quickly they were consumed, and whether they were consumed on 

a full or empty stomach. According to the expert, once all of the alcohol has been 

fully absorbed, the liver will eliminate the alcohol at a constant rate of 0.015 grams 

per 100 milliliters per hour.

The expert made two assumptions: (1) that appellant was eliminating alcohol 

from his system at the time of the blood draw, and (2) that the accident occurred 

one and half hours before the blood draw.8From these assumptions and his stated 

 

arguments, the trial court advised the jury that the exhibits, if requested, would be delivered to 

the deliberation room: “I’ll remind you again that if you want to see the evidence, you can ask 

for any or all—any or all of that, and we’ll send it into the jury room with you.” There is no 

record that the jury made a request, and the trial court did not note a request in any of its docket 

sheets.

Even if the medical records had been requested, there is no showing that the jury would 

have known how to interpret them. The meaning of “hematologic” is unlikely to be within the 

common understanding of a lay juror. Furthermore, the records clearly denoted that appellant 

had a “High” count of “WBC”—white blood cells, we presume. A juror could have seen the 

records and concluded that appellant’s blood cell count was higher than average.

8

There is no concrete evidence that the accident actually happened one and a half hours 

before the blood draw. The expert was simply asked to conduct his analysis assuming that time 

lapse. From the live testimony, we know that the eyewitness who saw the accident was traveling 

on the interstate between 11:00 p.m. and midnight. The eyewitness did not testify about the exact 

time that he saw the accident, but a first responder testified that the accident happened “just 

before midnight.” As for the other time point, the evidence is much clearer: a nurse testified that 

she drew appellant’s blood at the hospital at 1:05 a.m.
25

formula, the expert estimated that the BAC of appellant’s whole blood at the time 

of the accident was 0.133.

The expert did not explain in detail how he arrived at that figure, nor did he 

provide a factual basis for assuming that appellant was in the elimination phase. 

The expert testified that a person normally enters the elimination phase within two 

hours of his last drink, but there was no evidence indicating when appellant last 

consumed an alcoholic beverage. Nor was there any evidence of whether appellant 

had been drinking on a full or empty stomach. By assuming that the accident 

happened an hour and a half before the blood draw, the expert failed to realize that, 

without more information, a conclusion could not even be made that appellant had 

entered the elimination phase by the time he arrived at the hospital.

D. Other Relevant Factors

We first note that the expert struggled to perform his calculations, which 

were “on the fly,” as he described them. The trial court had to excuse the expert 

from the courtroom, and the expert returned to give his calculations after another 

witness took the stand.

We also note that, if appellant had been in the absorption phase at any point 

between the time of the accident and the blood draw, then the BAC of his whole 

blood at the time of the accident would have been equal to or less than the BAC of 

his whole blood at the time of the blood draw. This is true regardless of the 

conversion ratio that is used.

E. Analysis

It is clear that the jury determined that appellant was driving, but it is not 

clear under which theory it found that he was intoxicated. There was a conflict in 

the evidence under the impairment theory. There was also a conflict under the per 
26

se theory; the jury heard testimony that the BAC of appellant’s whole blood could 

have been above or below 0.08, depending on which sorts of assumptions were 

made.

The expert’s testimony demonstrated that many variables must be accounted 

for when trying to establish that a person is intoxicated per se. But under the trial 

court’s erroneous view of the law, none of those variables needed to be considered

in this case. The trial court’s charge error, when combined with the State’s 

improper argument, allowed the jury to convict appellant solely on the basis that 

the BAC of his blood plasma exceeded the per se limit. We conclude that this error 

resulted in some harm because it completely obviated the jury’s need to examine 

appellant’s alternative defense, and there was affirmative evidence in support of 

this defense showing that appellant was not impaired. See Anderson v. State, 774 

S.W.2d 733, 735 (Tex. App.—Houston [14th Dist.] 1989, no pet.) (erroneous 

instruction on the per se theory of intoxication was harmful, even though there was 

sufficient evidence to convict under the impairment theory of intoxication); cf. 

Bagheri, 119 S.W.3d at 763–64 (erroneous admission of retrograde extrapolation 

testimony was harmful, even though there was sufficient evidence to convict under 

the impairment theory of intoxication).

CONCLUSION

The evidence is legally insufficient to support a conviction for a Class A 

misdemeanor for driving while intoxicated. We render a judgment of acquittal as to 

this offense, meaning that the State is barred from retrying it. See Ex parte 

Granger, 850 S.W.2d 513, 518 (Tex. Crim. App. 1993).

There is sufficient evidence to support a conviction for a Class B 

misdemeanor, but because we conclude that the trial court committed harmful 
27

errors with respect to this offense, we reverse the court’s judgment and remand the 

case for a new trial.9

/s/ Tracy Christopher

Justice

Panel consists of Chief Justice Frost and Justices Christopher and Busby. (Frost, 

C.J., dissenting).

Publish — Tex. R. App. P. 47.2(b).

 

9

This disposition makes it unnecessary to address appellant’s fourth issue, in which he 

argues that the trial court imposed an unconstitutional condition of community supervision.