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My AccountChapter 49
- 49.1 Definition of “Intoxication”
- 49.2 Definition of “Motor Vehicle”
- 49.3 Definition of “Operate”
- 49.4 “Synergistic Effect” Instruction
- 49.5 “No Defense” Instruction
- 49.6 “No Culpable Mental State Requirement” Instruction
- 49.7 “Refusal” Instruction
- 49.8 Limited Use of Breath Test Evidence
- 49.9 “Involuntary Intoxication” Defense Instruction
- 49.10 Necessity Defense Instruction
- 49.11-49.15 Reserved
- 49.16 Instruction—Misdemeanor Driving While Intoxicated (with Necessity Defense)
- 49.17 Instruction—Driving While Intoxicated with Child Passenger
- 49.18 Instruction—Misdemeanor Flying While Intoxicated
- 49.19 Instruction—Misdemeanor Boating While Intoxicated
- 49.20 General Comments on Felony Enhanced Offenses
- 49.21 Instruction—Felony Driving While Intoxicated (Two Prior DWI Convictions)
- 49.22 Instruction—Felony Driving While Intoxicated (Prior Intoxication Manslaughter Conviction)
- 49.23 General Comments on Death or Injury Intoxication Offenses—Causation
- 49.24 Instruction—Intoxication Manslaughter
- 49.25 Instruction—Intoxication Assault
Comment
In those cases in which the state has not introduced retrograde extrapolation evidence regarding what the breath test results suggest was the defendant’s alcohol concentration at the time of the driving, the jury might be instructed as follows:
You are instructed that evidence of the breath test administered to the defendant was admitted for the sole purpose of showing, if it does, that the defendant consumed alcohol. You are not to consider the breath test as evidence of the defendant’s alcohol concentration, if any, at the time he was driving.
In State v. Mechler, 153 S.W.3d 435 (Tex. Crim. App. 2005), the court of criminal appeals indicated the following:
We recently held [in Stewart v. State, 129 S.W.3d 93, 97 (Tex. Crim. App. 2004)] that intoxilyzer results are probative without retrograde extrapolation testimony. Mechler’s intoxilyzer results indicate that Mechler had consumed alcohol. As a result, they tend to make it more probable that he was intoxicated at the time of driving under both the per se and impairment definitions of intoxication. Mechler concedes that this factor weighs in favor of admissibility.
Mechler, 153 S.W.3d at 440.
Mechler held that the trial judge erred in excluding intoxilyzer results offered without extrapolation testimony under Texas Rule of Evidence 403 balancing analysis.
Neither Stewart nor Mechler determined whether, when breath test evidence is admitted without extrapolation testimony, it is best limited to consideration on whether the defendant consumed alcohol. The instruction suggested above would so limit it.
Proponents of an instruction as set out above also contend that when such extrapolation evidence has not been produced, the jury should not be instructed that it may find the defendant intoxicated by reason of having an alcohol concentration of 0.08 or more, even if this was alleged in the charging instrument.