Dateline: September, 2007, Issue 4
Deposed witnesses are not always available for trial, and so the testimony is read by a reader selected by the attorney presenting the witness' testimony. Jurors judge more than the content of the read testimony - they also judge the reader.
Kassin (1983) found that opinions of a witness are influenced by the demeanor of the deposition testimony reader. Jurors heard a skillful reader (e.g., an actor) read deposition testimony. For half of the jurors, the reader's demeanor was polite, attentive, cooperative and unhesitating in response to questions. For the other half of the jurors, the reader presented the same testimony with a demeanor that was impolite, often annoyed, cautious and fumbling in style. The actor read the same transcript for all jurors, varying only tone of voice, facial expressions and body language.
Even though jurors were told the reader was not the actual witness, the demeanor of the reader affected jurors' perceptions of testimony credibility and jurors' verdicts.
Jurors evaluated the witness as more credible when the reader used a positive, rather than a negative, demeanor to read the very same deposition testimony. When read with a positive demeanor, jurors judged the testimony as more believable, accurate and persuasive.
Jurors also were more likely to return a favorable verdict when the deposition testimony was read with a positive, rather than a negative, demeanor.
A messenger effect exists, wherein the messenger affects the message that jurors receive. Jurors are unable to separate witnesses and their testimony from the messengers who deliver it.
Source Kassin, S. M. (1983). Deposition testimony and the surrogate witness: Evidence for a 'messenger effect' in persuasion. Personality and Social Psychology Bulletin, 9, pp. 281-288.