Back when I was trying cases regularly, I developed a little courtroom hobby.
Police officers would take the stand and slip into what I can only describe as cop speak. Something happens when someone sits in the witness chair and suddenly every ordinary human verb in the English language becomes… robotic.
“Upon surveillance, I observed the male entering and exiting the establishment on multiple occasions.”
I’d pause.
“You mean you watched him going in and out of the store?”
The jurors would chuckle.
Or this one:
“The suspect alighted from the vehicle.”
“You mean he ran away from the car?”
Another chuckle.
It became a sort of gentle translation service. The officer wasn’t trying to mislead anyone. It’s just that somewhere along the way, a plain sentence like I saw him run away from the car becomes transformed into something that sounds like it belongs in a police procedural.
The jurors always appreciated the translation. Not just because it was funny, but because it made the testimony feel… normal, human again.
At the time I thought I was simply doing the jury a favor. It turns out cognitive science says I may have been doing something much more important.
A recent study tested how legal jargon affects the way jurors process information and make decisions.[1] Researchers gave over 1,000 participants a fictional trial transcript describing expert testimony in a financial fraud case.[2] The participants were randomly assigned to read one of two versions of the exact same testimony.
One version used standard legal and technical language:
“insolvency litigation,”
“fraudulent conveyances,”
“embezzlement,”
“escheatment reporting.”
The other version replaced those terms with ordinary language:
“bankruptcy trials,”
“debt transfers,”
“theft,”
“property reporting.”
The information in both transcripts was identical. Same facts. Same testimony. Same length. Only the language changed.
After reading the testimony, participants had to do what jurors do: decide whether the defendant was guilty and report how confident they felt in their decision.
Here’s where things get uncomfortable: The jargon didn’t just make the testimony harder to read. It changed the way people judged the defendant.[3]
First, the obvious finding: jargon made the testimony harder to process. Psychologists call this processing fluency, the subjective experience of how easy or difficult something is to understand.[4] When information flows smoothly, we feel confident and comfortable. When it doesn’t, our brains start sending little warning signals that something is off.
But here’s the twist: When the testimony felt harder to process, jurors were more likely to vote guilty.[5]
Let that sink in for a moment.
Nothing about the facts changed. The evidence didn’t change. Only the language changed.
Yet when the language became more technical and jargon-heavy, jurors became more inclined to convict.
Why?
Because our brains are terrible at diagnosing the source of our own mental discomfort. If something feels difficult to process, we instinctively look for an explanation. But instead of thinking, this testimony is hard to understand, we often leap to a different conclusion entirely:
Something about this situation feels suspicious.
And sometimes that suspicion, “that metacognitive discomfort can be misattributed not just to the message or the self, but to a third party: the defendant.”[6]
In other words, jurors may subconsciously blame the person on trial for the fact that the testimony itself is difficult to follow.
But Wait a Second… That’s Not What I Did
Now here’s the part that made me pause when I read the study.
If jargon makes jurors more likely to convict, then my little translation routine should have been a terrible strategy.
After all, I was the prosecutor. The police officer was my witness. If robotic police jargon nudges jurors toward suspicion, maybe I should have just let him keep sounding like RoboCop.
Instead, I did the opposite. I translated him.
“Upon surveillance I observed the male entering and exiting the establishment.”
“You mean you watched him going in and out of the store?”
Why would simplifying the language help my case if the research suggests that disfluency nudges jurors toward guilt?
The answer, I think, lies in the difference between momentary suspicion and overall persuasion.
Yes, jargon creates cognitive friction. When information feels hard to process, people sometimes misattribute that discomfort to the situation or the defendant. That may be why disfluency nudged some participants toward guilty verdicts in the experiment. But disfluency also produces a host of other downstream effects: jurors feel less confident in their decisions, less capable of serving as jurors, and less trusting of the judicial system.[7]
None of those things are good for persuasion.
Jurors who feel confused are not happy jurors. Jurors who feel incompetent are not engaged jurors. And jurors who feel alienated from the process are not particularly receptive to the case you’re trying to present.
By translating the officer’s testimony into ordinary language, I was doing two things at once:
- Reducing cognitive friction so jurors could actually process the evidence.
- Building credibility by signaling that we weren’t trying to hide behind fancy language.
And that combination – clarity plus credibility – turns out to be a powerful persuasive tool.
Now, to be fair, lawyers use jargon for a reason. Technical terms can be precise, efficient, and meaningful within a professional community. Among lawyers, saying “res ipsa loquitur” or “fiduciary duty” can sometimes be quicker than explaining the concept from scratch.
But jurors aren’t members of that community.
To them, jargon is just friction. And cognitive friction rarely helps persuasion.
A Quick Word About Expert Witnesses
If this research makes anyone uncomfortable, it should probably be expert witnesses.
Experts live in jargon. Their professional credibility is built on technical vocabulary that signals training and expertise. And sometimes that vocabulary is genuinely necessary.
But the study suggests that every layer of technical language adds cognitive burden for jurors. When that burden grows too large, jurors stop evaluating the evidence itself and start reacting to how difficult the testimony feels to process.
That reaction can show up in strange ways – reduced confidence, disengagement, or misplaced suspicion.
Which means the most persuasive expert witness may not be the one who sounds the most technical.
It may be the one who can explain the science as if they were talking to a smart neighbor across the fence.
A Teaching Moment for Advocacy Classrooms
For those of us who teach trial advocacy, the lesson seems pretty clear.
Law students often equate professionalism with formality. The more technical the vocabulary, the more “lawyerly” they feel. “Look, Ma, I used a ‘wheretofore!’”
But jurors aren’t grading them on how well they sound like a legal treatise.
Jurors are trying to understand a story.
The advocates who win that contest are usually the ones who strip away the linguistic clutter and make the facts easy to process.
In other words, the goal isn’t to sound smart. The goal is to make the jury feel smart.
And sometimes the most powerful question in a courtroom isn’t complicated at all.
“You mean he ran away from the car?”
[1] Olivia M. Bullock, Jargon, Fluency, and Judgment: How Legal Jargon Shapes Juror Decision-Making, Journal of Applied Communication Research (2026).
[2] Id. at 6.
[3] Id. at 9.
[4] Id. at 2.
[5] Id. at 9.
[6] Id. at 13.
[7] Id. at 11.