Adults with developmental language disorder (DLD) are more likely to be judged as guilty in criminal mock trials, regardless of their actual guilt, according to a new UConn study published in the Journal of Communication Disorders. 

The study, led by Tammie Spaulding, associate professor of speech, language, and hearing sciences, suggests that language impairment may influence the perceptions of jurors and other legal professionals in the criminal justice system. 

“We know there’s a high prevalence of communication disorders, including developmental language disorder, in the incarcerated population,” Spaulding says. “However, we don’t know if individuals with these disorders are more likely to commit crimes due to other risk factors associated with the disorder, or if there’s bias against them because they struggle to use strong communication skills to convey their innocence.” 

Developmental language disorder is a neurodevelopmental condition characterized by impaired language functioning with no clear cause. People with DLD often struggle with vocabulary, sentence structure, and the ability to organize and recall events. 

“It is more common than autism spectrum disorder, but very few people know about it,” Spaulding says. “Unlike someone who has a hearing difference or an acquired brain injury like a stroke, the language deficits of those with developmental language disorder can’t be explained by something else.” 

Spaulding, who studies DLD in youth and adolescents, conducted her most recent research with Audra Blewitt ’17 (CLAS), a Phoenix-based clinical speech-language pathologist who specializes in working with children.  

According to Spaulding, previous studies have shown that individuals with DLD represent between 7% and 12% of the general population but are disproportionately represented in the criminal justice system. 

In this study, researchers wanted to explore whether jurors were more likely to wrongly judge individuals with DLD as guilty potentially due to their language impairments.  

Twenty-four adult participants—12 with DLD and 12 with typical language abilities—were placed in mock crime scenarios, with some being guilty and others innocent. Peer jurors watched video interrogations of all participants and were asked to determine whether the individuals were guilty or not guilty based on their responses.  

The study found that while half the participants in both groups were guilty, jurors were significantly more likely to judge innocent individuals with DLD as guilty compared to those without the disorder. Additionally, participants with DLD struggled more to convince jurors of their innocence. 

Spaulding says the findings suggest that communication challenges faced by adults with DLD—such as difficulties organizing their thoughts, using accurate and precise vocabulary, and providing coherent narratives—may lead jurors to interpret their responses as evasive or deceptive.  

Spaulding added that jurors were generally confident in their judgments, even though they were wrong about half the time.  This overconfidence highlights a potential problem in the criminal justice system: individuals with DLD may be unfairly judged.  

Spaulding says these findings have serious implications for how individuals with DLD are treated in legal contexts.  

For instance, those with DLD may struggle to meet the linguistic demands of an interrogation—such as recalling details or providing a coherent narrative—which could lead to their perceived guilt. As a result, they may face biased judgments. 

She says it’s important for professionals in every part of the legal process, from police officers to lawyers, judges, and jurors, to understand and recognize DLD and the challenges it presents. 

Spaulding notes that even for the average person, fully understanding the jargon used throughout the legal process can be difficult. She adds that despite growing up around lawyers and being immersed in this work, she sometimes struggles herself. In one instance, she watched a legal proceeding involving a child and says she couldn’t understand around 30 percent of the language being used. 

“There are so many people who encounter our legal system that don’t know what’s going on because of the jargon that’s being used,” she says. “There’s a big plain language movement out there to try to simplify the language used to provide accessibility for everybody, whether you have a language disorder or not.” 

The plain language movement is a loosely organized campaign to encourage legal and business writers to write clearly and without jargon, so a broad audience is able to understand.  

Spaulding recalled a previous study where adolescents with DLD, despite knowing their Miranda rights, struggled to fully understand them. 

“They didn’t make the right inferences,” Spaulding says. “They didn’t understand that if they started talking with the right to remain silent, they could stop at any time… but I think even more importantly, what came out in that study is that a high proportion of adolescents with typical language skills didn’t understand their Miranda rights either.” 

The study calls for greater awareness of DLD and suggests accommodations such as interpreters to ensure that those with the disorder are treated fairly. 

“We should assume that everybody has a language disorder, instead of trying to put financial resources into assessing the language functioning of every person who interacts with someone in the legal system,” she says. “It’s a much better approach to assume that everyone has a language disorder and adjust accordingly.”