A school resource officer’s interpretation of a boy’s body language was an acceptable piece of testimony in the trial of the boy’s relative, the Colorado Supreme Court decided by 6-1 on Monday, reversing a lower court’s finding that the officer inappropriately relied on his professional expertise to characterize the non-verbal response.

“Certain types of body language, like the myriad hand signals of a Colorado Rockies third base coach or the gestures of the conductor of the Colorado Symphony, may lie outside an ordinary person’s knowledge and experience,” wrote Justice Maria E. Berkenkotter in the majority opinion. “Other types of body language, however, are very familiar to ordinary people because everyday social interactions present countless opportunities to observe body language and ascribe meaning to it.”

Daniel P. Rubinstein, the district attorney for Mesa County whose office originally handled the case, agreed that non-experts are accustomed to interpreting people’s honesty based on body language.

“To say that only an expert would be permitted to describe how a person’s body language affected their view of the person’s credibility lacks recognition that testimony at a criminal trial still involves people presenting things that occurred in the real world,” he said following the Court’s ruling.

In the case at hand, a 15-year-old boy admitted to his school counselor he had attended a concert the previous night with his 35-year-old relative, Justine Lynn Murphy. He also stated he used methamphetamine while partying with her. The boy subsequently went to the hospital for evaluation.

While there, the school resource officer, Mesa County Sheriff’s Deputy Mark Johnson, questioned the boy in the presence of his father. The student reaffirmed that he injected methamphetamine, and Johnson then asked whether he got the drugs from Murphy.

According to Johnson’s testimony at trial, the boy did not answer but instead “his body language changed” and he looked “down and away.” Johnson then asked if Murphy gave him or sold him the methamphetamine.

“She sold it to me,” the boy responded. His father then ended the interview.

Prosecutors charged Murphy with distributing a controlled substance and contributing to the delinquency of a minor. A jury convicted her in 2016.

However, at her trial, the boy altered his story of obtaining the drugs, saying he got them from a dealer friend at the concert and used them the subsequent morning prior to school. He refused to identify the friend. Further, the boy testified he shook his head “no” when Johnson asked if Murphy gave him the methamphetamine.

Johnson stood by the original version of events, and despite objections from Murphy’s attorney, gave his opinion on what the boy’s non-verbal reply meant to him.

“I took that, based on my training and experience, to be that he just really didn’t want to answer me, because — and that was an affirmative [answer],” the deputy said. He elaborated: “I believed that he did remember, he just didn’t want to tell me so that’s why I changed, instead of giving him an open-ended question of who’d you get it from, I just asked him directly, did you get it from [Murphy], and his body language changed, leading me to believe that that was an affirmative.”

Murphy appealed her convictions, arguing to the Court of Appeals that while an ordinary witness may give their opinion on another person’s behavior, a witness who testifies based on training or experience constitutes expert testimony. A three-member appellate panel concluded, based on cases from other jurisdictions, that Johnson relied on his training to believe the boy was being deceptive.

The trial court “essentially allowed Deputy Johnson to tell the jury that, even though [the boy] was telling a different story at trial, his training and experience enabled him to determine which version was correct because he was able to see and interpret [the] body language during the initial interview,” wrote then-Judge Daniel M. Taubman.

In the panel’s judgment, the only real evidence suggesting Murphy gave her relative the drugs was his hospital bed statement. Therefore, the deputy’s testimony about the boy’s body language was actually an important piece of information that the trial court should not have permitted.

Prosecutors turned to the Supreme Court, arguing the boy’s movements had a “well understood meaning.” A majority of the Court acknowledged it is difficult to distinguish for police officers when they rely upon personal experience versus professional experience. However, in this instance, the justices believed Johnson made a judgement that an ordinary person could have also made.

“[T]he non-verbal response at issue here is the type of body language that ordinary people have likely experienced. Anyone who has interacted with children, for example, could infer that a child who looks away or avoids eye contact when confronted about their misbehavior (‘Did you take the cookie?’ ‘Did you hit your brother?’) may be tacitly acknowledging that misbehavior,” Berkenkotter explained in the court’s opinion.

However, “it was not because of his training and experience that he was able to observe and form an opinion about [the boy’s] body language,” she added. The majority also concluded it was not problematic that Johnson had prefaced his testimony by referencing his training and experience.

Chief Justice Brian D. Boatright wrote separately to say he agreed with the majority, but for a different reason. To him, the deputy was not offering an opinion at all about the boy’s honesty, and was instead explaining why he asked a direct follow-up question after receiving a non-verbal response.

The dissenting opinion from Justice Richard L. Gabriel, by contrast, contended that not only did the officer’s interpretation stem from his professional experience, but the lack of physical evidence and subsequent contradictory testimony from the boy meant the officer’s body language analysis likely played an outsize role in the jury’s verdict.

In disagreeing with his colleagues, Gabriel wrote that Johnson went beyond describing what he observed, and instead interpreted the boy’s movements to indicate deception, a desire to not answer, and ultimately an affirmative statement that Murphy gave him methamphetamine.

“In my view, this was not the kind of testimony that could be expected based on an ordinary person’s experiences or knowledge,” Gabriel found. “In the facts and in the context presented here, it was opinion testimony, based on the deputy’s specialized training and experience (particularly relating to witness interviewing), as to the meaning of a witness’s body language in the context of a police interrogation, and it was therefore expert testimony.”

The majority reversed the appellate panel’s decision and upheld Murphy’s convictions. Gabriel stated he would have awarded Murphy a new trial based on the dearth of other compelling evidence.

Rubinstein, the district attorney, applauded the majority’s decision as a “more practical approach” than the Court of Appeals’ ruling.

The case is People v. Murphy.