Law and Order: Under the influence?

Research explores how alcohol impairs understanding of Miranda rights, leads to self-incrimination

July 16, 2024 at 11:00am

A man crashes his car while fleeing the police. He is arrested and read his Miranda rights — constitutional rights that allow one to choose to not answer an officer’s questions and to request an attorney — then goes on to say things that could be considered incriminating. At the time of arrest, his blood alcohol level is 0.291, nearly three times the legal limit. His speech is slurred. And he’s having trouble standing. Is everything he says still considered legally admissible in court?

Yes, says FIU associate professor of legal psychology Jacqueline Evans, who works to better understand real life cases, like this one, where alcohol intoxication might jeopardize a suspect’s constitutional rights.

“People might assume if you’re drunk, you can’t be questioned by the police until you’re sober, but they would be wrong,” Evans explains.

“You can, in fact, be questioned and waive your right to counsel or silence while intoxicated, and everything you say can be used against you in court.”

Examining if these constitutional rights are working as they are intended — to protect suspects from making incriminating statements — is a complex puzzle. So, piece by piece, Evans constructs a clearer picture of how intoxication factors into what happens to people in the criminal justice system.

Evans' research tackles urgent questions exploring how intoxication may negatively impact a suspect’s comprehension and decision-making abilities, as well as how intoxicated statements are perceived by potential jurors. She recently found that even at lower levels of intoxication, suspects may not fully grasp or understand their Miranda rights, meaning they might not be able to enact or use those rights to protect themselves. At the same time, intoxicated suspects are likely to make incriminating statements, even if they are innocent, during interrogation.

Know your rights?

It almost goes without saying: Sober people will have a markedly different mindset and mood compared to someone who has had a few drinks. Alcohol slows cognitive processing, making it harder to think and focus.

However, intoxicated people often get the same treatment as sober suspects. Evans previously surveyed police departments and found many frequently encounter intoxicated people and apply the same protocols normally used with sober suspects. That begins with reading a suspect their Miranda rights.

Decision-making relies on a solid comprehension of one’s decisions — and that begs the question whether someone who’s drunk can “knowingly and intelligently” decide to voluntarily waive their rights.

Evans and a collaborative team of researchers led one of the first studies to find out.

To test Miranda rights comprehension, study participants were split up into groups, including a sober group and an intoxicated group with a breath alcohol content of .07 percent — lower than the .08 driving limit, and drastically lower than seen in court cases where defendants were considered lucid enough to comprehend and waive their rights.

Even with low levels of intoxication, the intoxicated group scored lower compared to the other group and had a difficult time explaining the meaning of Miranda warnings, according to the results published in Law and Human Behavior.

“This shows alcohol can impact someone’s ability to understand the basics, like that they have the power to stop questioning at any time,” Evans said.

More data will be needed, Evans points out, to provide law enforcement and the courts with more evidence-based recommendations so they can make informed decisions about whether any changes happen, like imposing ‘wait limits’ to allow suspects time to sober up before they are even read their Miranda rights.

Intoxication and incrimination

First comes the reading of the rights, then interrogation. Just as intoxicated suspects can be read their Miranda rights, they can also be questioned and interrogated.

It’s a routine practice. Evans’ police survey found 70% of police had interrogated at least one intoxicated suspect. One of the biggest concerns is that statements can be viewed as suspicious, false or even as confessions. A well-known example of this is in the story of Eugene Vent — one of the “Fairbanks 4,” innocent men convicted of the murder of John Hartman.

What are Miranda rights?

Miranda rights are constitutional rights that allow one to choose to not answer an officer’s questions and to request leglt counsel. They are intended to be clear, direct and easily understandable: "You have the right to remain silent. Anything you say can and will be used against you in a court of law. You have the right to an attorney. If you cannot afford an attorney, one will be provided for you. Do you understand the rights I have just read to you? With these rights in mind, do you wish to speak to me?"

According to the Miranda v. Arizona — the case that established the reading of these rights — a suspect’s statements can make it into court if the suspect makes an informed decision, choosing to “knowingly, intelligently and voluntarily” waive their rights to silence and to an attorney. The court intended to protect suspects’ constitutional rights and reduce the chance of any incriminating statements before an official interrogation.

Today, there are few studies on alcohol’s influence on suspects’ behavior and decision-making during interrogation. Evans and her team are the first to investigate this topic.

Study participants were put into a room with another person and given a test. They were instructed to work alone, not ask for help.

In one scenario, the other person claimed to be stuck on a question and asked the study participant for help. If they shared their answer — and some did — they were considered ‘guilty.’ In the other scenario, the person didn’t ask for help, and so the participant was automatically ‘innocent.’

After the assignments were submitted, someone from the research team approached both ‘guilty’ and ‘innocent’ participants and claimed there were identical wrong answers on the tests — a sign of cheating. The interrogation began.

“We looked at anything they said that could be seen as suspicious,” Evans said. “Maybe they didn’t outright admit they gave the answer and maybe they weren’t even guilty, but if they said something like ‘I didn’t cheat, but maybe the other person did,’ in a real interrogation, the interrogator would jump on that, thinking the suspect knew something.”

The intoxicated group incriminated themselves the most, according to the findings recently published in the Journal of Applied Research in Memory and Cognition. More than 80% made incriminating statements. Even if they were innocent.

In court

If intoxicated suspects incriminate themselves, regardless of guilt, it presents even more questions surrounding the impact of those statements in court.

That’s why Evans looks at those pivotal early moments at the time of arrest and interrogation — and the outcomes. Doing that requires getting into the heads of the people that determine a suspect’s fate.

“We wanted to find out what people even think about interrogating drunk people, because we don’t have that information — it is important to know what potential jurors are thinking,” Evans said.

The research team was well-aware an intoxicated person’s statements or confession could be interpreted in different ways: Honest — since alcohol is considered a great truth serum that also lowers inhibitions — or a little off, with intoxicated suspects coming across as more vulnerable, open to manipulation and coercion.

Results skewed in the latter direction. People viewed interrogations with intoxicated suspects as not exactly the best idea, because regardless of guilt or innocence, they thought suspects could be more likely to confess. While people didn’t believe intoxicated confessions were necessarily untruthful, they said there was reason to discount the statements in court.

This is invaluable information for both defense and prosecuting attorneys. It will remain important, at least as long as intoxicated suspects’ statements are inadmissible in court. For that to happen, more research is needed on how intoxication impacts the reliability of a suspect’s statements.

Now what?

Recent data links alcohol to more than half of the U.S. prison population. Suspects were either intoxicated at the time of the crime, had a history of alcohol abuse or had sought out treatment.

Facts like that aren’t enough to change the way the system functions. That’s why Evans keeps examining this issue from every angle, constantly questioning and challenging assumptions.

When a suspect’s constitutional rights are protected, any information that is gathered during questioning and interrogation is more likely to be convincing to jurors once it reaches the trial level, Evans says.

“And the more we know about alcohol’s impacts, the more empirical evidence we have to present to law enforcement and the courts so they can make informed decisions in cases involving intoxicated suspects in the interests of justice for all.”

Meet the researcher

Jacqueline Evans conducts research on investigative interviewing in its many forms and addresses the ability to detect deception in a variety of contexts. Evans collaborates on projects with other faculty members, students and partners at FIU's Global Forensic and Justice Center (GFJC). She hopes her research findings will help to inform professionals in various legal and national security contexts regarding the most effective methods to use when engaging in an investigative interview and assessing interviewee credibility.