If you are going to trial in a criminal case the State may be calling one or more expert witnesses to the stand. For example, in a DWI case with a blood test, the State may call a toxicologist to explain the blood results to the jury. Defendants have the right to question the expert witness before they testify and ask about the underlying facts or data that form their expert opinion per Texas Rule of Evidence 705(b).
What’s a 705(b) hearing?
The Rules of Evidence also provide that a criminal defendant must be permitted to “examine the expert about the underlying facts or data.” TEX. R. EVID. 705(b).
When do you have a 705(b) hearing? Is the jury present for hearing?
A 705(b) examination must be conducted before an expert states an opinion or discloses the underlying facts or data. The jury should be excused and not be present during the hearing.
What’s the purpose of the hearing again?
For the defendant the chance to voir dire the expert witness and determine the foundation of the expert’s opinion without fear of eliciting damaging hearsay or other inadmissible evidence in the jury’s presence. Alba v. State, 905 S.W.2d 581, 588 (Tex. Crim. App. 1995).
What is the court denies a 705(b) hearing trial?
It’s error, but it’s the kind of error (non-constitutional) our appellate courts routinely ignore. Rule 705(b) is mandatory, but a denial of a timely and proper motion for such hearing constitutes is only a non-constitutional error. See Trevino v.State, No. 04–12–00840–CR, 2014 WL 3518098, at *2 (Tex. App.—San Antonio 2014, no pet.) A non-constitutional will be disregarded on appeal unless it affects a defendant’s substantial rights. TEX. R. APP. P. 44.2(b).