Imagine a joint trial. The co-defendants, call them R and M, are tried for heroin trafficking on the basis of evidence found in a search of an apartment they shared. They elect not to testify. Both watch the proceeding quietly. During their deliberations, the jury sends a question to the judge: “Can we take the defendants’ body language into consideration? As evidence?” Over R’s lawyer’s objection, the judge instructs the jury: “While not evidence, the jury is entitled to consider any observations you made of the defendants’ demeanor during the trial.” The jury convicts R and acquits M.
This may sound like a law school hypothetical, but it is not made up. Carlos Ruiz and Yaritza Munoz-Delacruz were tried in Massachusetts in 2020 on drug charges stemming from a raid on their apartment. His name was on the lease; the utilities were in her name. Neither took the stand, and there was no record evidence that either did anything unusual in the courtroom. The jury’s decision to ask the judge whether they could consider the defendants’ body language obviously indicated that courtroom demeanor had come up in their deliberations. The jurors either disagreed or were uncertain whether the law allowed them to take it into account. What they meant by “body language” is, of course, a matter of speculation. From their question, it seems that the jurors took their responsibilities seriously and wanted to follow the rules. In her colloquy with the attorneys, the judge made clear her belief that jurors always observe defendants during trial and take those observations into consideration. And relying on her understanding of Massachusetts law, she concluded that doing so was permissible and she so instructed the jury.
Ruiz appealed, arguing that allowing the jury to base their verdict on factors outside of the evidence presented at trial violated his due process rights and right to remain silent under the Fifth and Fourteenth Amendments. The Massachusetts appeals court, although sympathetic to his claims and aware of federal and state cases that supported his position, felt bound by its understanding of Massachusetts law and affirmed in an unpublished opinion. The Supreme Judicial Court denied further review. Ruiz now has a cert petition pending in the Supreme Court.
Will the Supreme Court take the case? Unlikely. The Court has shown little inclination to dive into evidence issues, even ones—as argued in the petition—on which the circuits and state courts have taken conflicting positions.
Should the Court take the case? Absolutely. The law has a demeanor problem, and this case offers a prime opportunity for the Court to provide clear guidance on a question that goes to the heart of trial fairness.
The law’s demeanor problem announces itself clearly in the instruction the judge gave to the Ruiz jurors that “although not evidence” they could “consider” their observations of defendants’ demeanor. While the instruction may seem strange—how can observations be “considered” yet not be “evidence”—this is precisely the way demeanor, or a witness’s outward appearance, is treated when witnesses do testify. As a preeminent American evidence theorist once explained, a witness’s demeanor—unlike other evidence, which must at a minimum be relevant to be admissible—is always assumed to be in evidence “without any definite rules as to its significance.” Indeed, “demeanor”—how a person looks, and sounds, and behaves on the stand—is viewed in our legal tradition a key element of confrontation and a key factor in the evaluation of credibility.
So, even though it is not treated as “evidence” demeanor functions as proof, both at trials and in pretrial proceedings. Studies have found that prosecutors consider demeanor in thinking about the strength of a case and what pleas to offer. When a jury or judge decides a case that turns on credibility, reviewability is limited on the ground that an appellate court cannot assess the demeanor of the witnesses based only on the paper record. In a nutshell, demeanor is like the trial system’s secret sauce– it decides cases, it makes credibility decisions unreviewable, but to reiterate, it is “not evidence.”
This might be unremarkable if “demeanor” were a reliable measure of truthfulness or an accurate signal of guilt or innocence. But it is not. Judgments about the significance of outward appearance, tone of voice, and behaviors are culturally coded. In the U.S. we may think we can know something meaningful about a person’s state of mind or truthfulness from their appearance. In other countries, such as China, people are much more likely to believe that outward appearance is a performance that does not reflect inner thoughts. Moreover, decades of research in psychology have uncovered no evidence that we can learn much, if anything, about a person’s truthfulness from nonverbal cues.
To the contrary, researchers have shown that “reading” demeanor is often little more than an exercise in comparing a viewer’s expectations of how a forthright person should look or sound with that of the person being evaluated. Those expectations are formed from associations with people we know and trust, and we call upon them when we form impressions of strangers. As neuroscience research has shown, people will draw inferences about others based on their facial composition itself—reading symmetry as a sign of reliability and a heavy brow as a sign of propensity for violence even though these features have no demonstrable connection to behavior.
The Ruiz case makes clear that demeanor matters and not simply for defendants who take the stand. Something about how Ruiz and Munoz-Delacruz looked or behaved during the trial led the jury to convict him and acquit her. Perhaps Ruiz made a gesture that reminded a juror of an overbearing cousin. Perhaps he seemed “thuggish” during trial. Or perhaps Munoz-Delacruz had a defeated look that reminded another of her beleaguered mother. Although it is axiomatic in U.S. law that “a defendant must be tried for what he did, not for who he is,” that central tenet is arguably violated in myriad small ways in every trial as the law focuses everyone from prosecutors and attorneys to judges and jurors on the quixotic task of reading demeanor. The distinguishing feature in this case is that not only did the defendants not testify, but the jury was told explicitly, in effect, that it could take the testimony of their perceived body language into account as it deliberated.
The fact that that body language testimony appears to have been outcome determinative makes the case exceptional. Demeanor usually operates in the shadows, swaying the minds of judges and jurors in ways that those fact-finders themselves may not recognize. In this case, by contrast, only because a conscientious jury called attention to its focus on the defendants’ body language do we have a glimpse into a process that is generally opaque. How many other trials are there in which the courtroom demeanor of a non-testifying defendant is the deciding factor in a conviction? We have no way of knowing, but it is fair to assume the Ruiz case is not an outlier. This is precisely why the case deserves attention from the Supreme Court.
If the Supreme Court does take the case, the Court is unlikely to dislodge demeanor from its hallowed role in credibility determinations of witnesses who testify. However, it should, at a minimum, take demeanor off of its pedestal when it analyzes the jury instruction in Ruiz. The point is not simply that a non-testifying defendant should not have his culpability hinge on jury impressions of his body language or that of his co-defendant. The problem is also that the instruction—versions of which are routinely applied to testifying witnesses—gives the jury no cautionary guidance about the shortcomings of demeanor as a guide to credibility or personality. Ruiz is an ideal vehicle for the Court to recognize those shortcomings. And in the course of righting a wrong to Ruiz, the Court has the chance to begin a long overdue reexamination of the privileged role of demeanor in our system of proof.