Offer of Proof; Preserving Error for Appellate Review under Rule 103(a) (2)

By: Houston Criminal Defense Attorney John Floyd and Paralegal Billy Sinclair


In a recent article (“False Forensics: An Attorney’s Worst Nightmare.” 05-01-09), we reported on the increasing problems associated with the specialized field of forensic science. Prestigious organizations and scientists are calling now for a National Institute of Forensic Science with strict standards and enforcement mechanisms set up to insure that only truthful and valid forensic evidence is used to convict criminal defendants. It was faulty forensic science and lack of professional standards that prompted a former Houston Police Department crime lab technician to testify falsely in the rape and robbery trial of Gary Alvin Richard in 1987. Richard was recently released from prison after serving 22 years on a life sentence for violent crimes he did not commit. He case marked the fourth criminal defendant wrongfully convicted in Harris County because HPD crime lab technicians either lied or misrepresented forensic evidence test results to produce criminal convictions for unethical county prosecutors.


In our “False Forensics” blog, we concluded by saying: “Because of all the recent revelations and developments in the forensic science system, criminal defense attorneys now have an increased responsibility to challenge all forensic evidence offered at a criminal trial; to demand the methods used for gathering, processing, and preservation of that evidence; and to request for discovery of all notes by any analysts testing the evidence. Defense attorneys can no longer take this evidence as ‘scientifically’ infallible. Not only must defense lawyers thoroughly cross-examine these pro-prosecution witnesses about testing methodology, they must also identify all the analysts and support personnel involved in the testing process. Finally, defense attorneys must press for disclosure of testing mistakes made by the testifying ‘expert’ as well as all other mistakes made by others in the crime lab for which he works. This information goes to the heart of ‘reliability’ of the expert testimony, an issue open to cross-examination in Texas criminals.”


A decision by the Texas Court of Criminal Appeals (“CCA”), Woodall v. State, issued on April 29, 2009 not only revised the manner in which expert testimony and evidence must be challenged but underscored the responsibility of defense counsel to properly object to this kind of testimony in order to preserve the issue for review. 1/ The Woodall case involved a DWI conviction obtained in Harrison County. The Sixth District Court of Appeals (“Sixth District”) had reversed his conviction on February 22, 2007. 2/ The Sixth District had seven other DWI cases pending before it at the time, all raising the same issue decided in the Woodall case. The Sixth District consolidated these seven cases and overturned the convictions in each on March 7, 2007. None of the seven cases were designated for publication. The CCA granted the state’s petition for discretionary review in all eight cases and consolidated them for one decision.


The issue upon which the Sixth District based its reversals involved the science associated with the Intoxilyzer 5000, a machine that tests samples of breath for alcohol content. The attorneys in all the cases, except for Woodall’s attorney, filed motions to cross-examine the State’s expert on the operation of the Intoxilyzer 5000 and each motion listed the following eight areas of concern about the internal workings of this breath testing machine:

  1. The simulator, which the state presents as proof that the machine is working properly on the date in question, is based on Henry’s Law. It requires that the simulator is maintained at a constant temperature, in a close container, and at a constant pressure. It simulates a person which is offered to give a sample of their breath [sic]. The human body is not a close container which prevents a constant pressure and the temperature of the breath is unknown to the machine.
  2. The partition ratio between the gas above the fluid and the substance in the fluid is incorrect as it relates to the partition ratio assumed by the machine and the temperature of the breath is unknown to the machine.
  3. The machine heats certain parts that are used to produce a result including the collection chamber to between 115 deg. To [sic] 145 deg. Which effects [sic] the breath sample by producing a false high.
  4. The temperature of the human breath is unknown to the machine and has no way [sic] of measuring the same in order to give an accurate result. The temperature of the breath is above 34 deg. The [sic] results will be a false high.
  5. A rise of three (3) deg. C will increase the results by a false high of .02. A body temperature of 37 deg. C is 98.6 deg. F. which is normal body temperature.
  6. The Intoxilyzer is not specific to Ethel [sic] alcohol and that others substances [sic] will indicate a false high in the results.
  7. The Intoxilyzer has a slop or tolerance or error factor of .02.
  8. That if the temperature of the simulator is unknown to the operator he would not be able to predict the simulator results.

The district court denied each of the motions, stating that it had tried many DWI cases involving the Intoxilyzer 5000 and had never heard “one shred of evidence from an expert that would indicate any problem with the machine.” In effect, the trial court ruled that the machine was patently reliable and, therefore, the court would not permit cross examination of the State’s expert about its reliability.

The CCA began its legal analysis with a discussion of the purpose of Rule 103(a)(2) of the Texas Rules of Evidence. This rule limits the scope of issues that may be appealed when a trial court either excludes certain evidence or limits its use. With respect to exclusion of evidence, Rule 103(a)(2) prohibits an error about the exclusion being presented on appeal “unless a substantial right of the party is affected” and the “substance of the evidence was made known to the court by offer, or was apparent from the context within which questions were asked.”

Rule 103(a)(2) provides two ways for defense counsel to make an offer of proof: either in a question-and-answer form, or in the form of a concise statement by counsel. If defense counsel elects the latter method of proof, the concise statement must include, as the CCA stated, “a reasonably specific summary of the evidence offered and must state the relevance of the evidence unless the relevance is apparent, so that the court can determine whether the evidence [was] relevant and admissible.”


The purpose of the evidentiary procedure involving offer of proof is to create a record from which an appeals court can determine whether the exclusion of any evidence by the trial court was erroneous and harmful. The CCA noted that an underlying purpose for the procedure is to give a trial judge an opportunity to reconsider his/her ruling after the actual evidence has been presented.


More than two decades ago the CCA, in Virts v. State, held that there is a distinction between the general evidentiary purpose of Rule 103(a)(2) and a case in which a criminal defense attorney is not permitted an opportunity to cross examine a State witness about matters that might affect the witness’ credibility. 3/ The Virts court held that in the witness credibility context a defense attorney is not required to show what his cross examination might establish, but instead state only the general subject matter of the cross examination, and if this is challenged by the State, demonstrate for the record what the testimony sought to be elicited is admissible. This line of cross examination invariably deals with issues that might affect a witness’ credibility with a showing of malice, ill feeling, ill will, bias, prejudice or animus on the part of the witness.

The CCA noted Virts that some confusion has evolved over the years concerning the distinction between the following two kinds of evidence: “the credibility of a witness’s testimony” and “a witness’s credibility.” The court pointed out that the former refers to the “substance of evidence” and the later refers to “personal characteristics of the witness.” The appeals court assumed responsibility for the confusion by using language in Virts that said  “certain subject matters that might [show] malice, ill feeling, ill will, bias, prejudice, or animus” might “affect the witness’s credibility.” The appeals court said it hope Woodall would “return to the correct statement of the distinction between Rule 103(a)(2)’s requirement for preservation of error and the narrow exception for subject matters which affect the witness’s credibility …”


The very essence of the Virtz decision, which involved a trial court preventing a defense attorney from cross-examining a witness’ mental health, was that “the right of cross-examination by the accused of a testifying State’s witness includes the right to impeach the witness with relevant evidence that might reflect bias, interest, prejudice, inconsistent statements, traits of character affecting credibility, or evidence that might go to the impairment or disability affecting the witness’s credibility.”

Virtz, therefore, dealt specifically with evidence that went to a witness’ credibility and not with evidence that might affect the substance of the witness’s testimony. The Sixth District construed Virtz differently in the DWI cases. “Clearly,” the court said, “questions [to the State’s expert] about the claimed shortfall in the [Intoxilyzer’s] capabilities … could have impaired the [State’s expert] credibility and would have been directed at raising doubts that the results about which he was testifying were accurate.”


The CCA disagreed with this overly broad Virtz interpretation. “While there might be little distinction between a witness’s credibility and the substance of the witness’s testimony in some case,” the CCA said, “we find no showing here. To the contrary, we find a clear distinction, because any shortfall in the machine’s capabilities would raise doubts about the substance of the witness’s testimony, but not about the witness’s credibility. Even if the evidence were presented that cast doubt on the Intoxilyzer 5000, this would not necessarily mean that the State’s expert had bias or prejudice, for example, in testifying against the appellant Woodall. Surely all cross-examination, to some extent, is directed at ‘raising doubts’ for the trier of fact about the witness’s direct testimony. But to equate the two would allow the exception to swallow Rule 103(a)(2) entirely.”


The CCA then set forth a strict clarification to the exception of Rule 103(a)(2): “where the defendant, in cross-examining a State’s witness, desires to elicit subject matters that tend to impeach the witness’s character for truthfulness—for example, to show malice, ill-feeling, ill-will, bias, prejudice, or animus on the part of the witness toward defendant—in order to preserve the issue for appellate review, he is not required to show that his cross-examination would have affirmatively established the facts sought, but merely that he desired to examine the witness with regard to those specific subject matters that tend to impeach the witness during his cross-examination.”


Against that legal backdrop, the CCA upheld the Sixth District’s decisions reversing seven of the DWI convictions because the trial court had impermissibly restricted cross-examination concerning the “reliability” of the Intoxilyzer 5000. The court, however, reinstated Woodall’s conviction because his attorney failed to properly preserve the issue for review under Rule 103(a)(2).


The State in Woodall’s case made an oral request for the trial court to take judicial notice of the science supporting the Intoxilyzer 5000. Defense counsel objected, telling the court that he would cross examine the State’s expert in a manner that would effectively challenge this science. The attorney argued that to prevent such a cross examination would “create a per se guilt issue on intoxication based upon breath testing.”


The trial court granted the State’s judicial notice motion, and Woodall’s attorney immediately sought a clarification of the court’s ruling. He questioned the court pointedly about the degree to which the trial court’s ruling restricted his right to cross examine the State’s expert. The trial court made it clear it would not permit any cross examination about the principles of breath testing. Woodall’s attorney objected once again, and the court once again overruled his objection. Defense counsel requested a running objection and stated he needed to perfect a bill. The trial court suggested that the attorney make a statement into the record of what he would prove through his cross examination. Defense counsel said he would do so later, but he never did.


That was a fatal procedural error as the CCA illustrated: “Although Woodall showed an intent to call into question the underlying science of the Intoxilyzer 5000, this intent does not amount to an intent to impeach the witness’s truthfulness, as opposed to the substance of the witness’s testimony. Because the appellant Woodall failed to ‘merely establish’ that the ‘general subject matter’ of his proffered evidence would be used to impeach the expert, and not the substance of the expert’s testimony, his case is controlled by the requirements of Rule of Evidence 103(a)(2) rather than the exception for impeachment of a witness’s credibility. Woodall failed to preserve his complaint for review by making a record of the substance of the evidence he wished to present as Rule 103(a)(2) required.”


The CCA underscored the importance of Rule 103(a)(2) by noting that the trial court and all the attorneys involved in these consolidated DWI cases were familiar with the questions posed to and answers given by the State’s expert in previous trials, but CCA pointed out that it was not “privy to such information.” The CCA said the only way it could adequately review and decide the admissibility of excluded evidence and whether the trial court abused its discretion in excluding that evidence was to have a record of the evidence before it as required by Rule 103(a)(2). The CCA then added that Woodall’s attorney’s failure to either “perfect a bill” or make a concise statement about what he would prove in his cross examination precluded the excluded evidence issue from being reviewed on appeal.


No doubt Woodall will be able to establish ineffective assistance in a habeas corpus proceeding. The CCA ruling that his attorney botched the excluded evidence issue would establish per se ineffectiveness, and the fact that the court agreed that the other seven DWI convictions should be reversed would establish a prejudice flowing from the ineffectiveness.  This will probably be greeted with cheer from his defense lawyer, as it could get his client a new trial.


The unfortunate thing about the Woodall case is that the attorney made a concerted effort to challenge the Intoxilyzer 5000 and knew he had to “perfect a bill” to have the trial court’s ruling reviewed on appeal, but simply forgot or neglected to perfect the bill as he told the court he would. It was a critical lapse that cost his client a reversal of his DWI conviction.

The maxim “never put off for tomorrow what you can do today” aptly fits the Woodall case. While the defense lawyer made a strong effort to object, an effort that should have satisfied the Court of Criminal Appeals, the defense attorney should have made a concise statement about what his proffered evidence on cross examination would prove the moment the trial court denied his second objection.


The Woodall case also exemplifies what we stressed in our “False Forensics” blog: a defense attorney must not only be willing to cross examine a State expert witness about the “substance” of his testimony but about his personal “credibility” as an expert witness as well. Defense counsel must be prepared to satisfy the evidentiary requirements of Rule 103(a) (2); namely, to show what the evidence he seeks to establish on cross examination would prove, and that it is relevant.



1/ Woodall v. State, ___ S.W.3d ____ (Tex. Crim. App. No. PD-0454-07, 04/29/09).
2/ Woodall v. State, 216 S.W.3d 530 (Tex.App.-Texarkana 2007)
3/ Virtz v. State, 739 S.W.2d 25 (Tex.Crim.App. 1987)

By: Houston Criminal Defense Attorney John Floyd and Paralegal Billy Sinclair