Rose Bialk/The Mossy Log
On March 16, the Oregon Supreme Court held appellate oral arguments at Lewis & Clark Law School, providing students and faculty a front row seat to legal deliberation at the highest level in the state. The court heard arguments for an appeal of the decision in State of Oregon v. Jeffrey Kurtz McMahon, a case involving questions about whether evidence gathered from McMahon, the defendant, should be barred from consideration due to a prior Miranda rights violation. The Mossy Log attended this event but due to court restrictions on recording, all quotations are reconstructed from contemporaneous notes and are accurate to the best of the reporter’s ability. An official transcript will be made available at a later date.
The Oregon Supreme Court held the appeals arguments on campus as a part of its efforts to connect Oregonians with the work of the state’s judicial system. It also allowed law students to see firsthand how questions at the highest level of state law are debated, an experience that textbooks and lectures cannot fully replicate. The visit underscores LC’s reputation as a hub for legal education and civic engagement in Oregon, connecting future lawyers directly with the state’s judicial process.
The case itself centers on McMahon, who was convicted of unlawful sexual penetration and sexual abuse in the first degree in 2025. Initially, McMahon’s case was brought to the Court of Appeals, where the Court decided against all three of the defendant’s arguments — they found that McMahon’s statement, the DNA evidence obtained, as well as the language used by a state expert in her report on the DNA evidence were all admissible in court. McMahon appealed this verdict, ascending to the state Supreme Court.
Under Oregon constitutional law, Miranda warnings must occur “when there is a significant risk that conditions created by the state could undermine a person’s ability and willingness to assert their constitutional rights to remain silent and have counsel present during a police interrogation.” The defense argued that McMahon had been misled by his probation officer during the initial interview, which concerned a suspected DUI rather than allegations of sexual assault, depriving the defendant of knowledge which would inform his decisions on whether to remain silent and have counsel present.
“The defendant was presented with a false premise,” defense attorney Ernest Lannet told the court. “The slate is not clean.”
The attorney argued that, because of the earlier questioning, McMahon may have believed he had already harmed his case.
“He thought, ‘what more harm could I do to myself?’”
The central legal question was whether McMahon’s subsequent interview with a different officer — after receiving fresh Miranda warnings — was sufficient to “clean the slate” and make any waiver of rights voluntary.
The prosecution contended that the second interview was fully lawful, and that investigators did not rely on any statements made during the misleading first interview. They emphasized that the DNA evidence, collected with consent, was valid and properly interpreted.
Justices heard arguments from both the defense and prosecution, exploring subtle nuances of police procedure and evidence interpretation under state law.
Justice Rebecca Duncan quickly sought clarification on a key point of agreement between the parties.
“So both parties are in agreement that there was an initial Miranda violation?” Duncan asked early in the argument.
Defense counsel confirmed that the earlier questioning had already been ruled improper because McMahon was misled about why he was being questioned.
Justice Christopher Garrett pushed back on how unusual such tactics might be.
“Deception with the police is normal, though, right?” Garrett asked, probing whether misleading a suspect necessarily invalidates later questioning.
Justice Stephen Bushong raised a related concern about how the earlier interview might have shaped McMahon’s mindset during the second one.
“He probably felt like he had to explain himself after the previous interview,” Bushong said.
The justices also spent significant time examining the DNA evidence presented at trial. Justice Bronson James JD ’03,an adjunct professor at LC Law School, questioned why the State insisted on describing the DNA results as a “match” rather than a “partial match.”
“Why did the State want the term ‘match’ so bad?” Garrett asked at one point, echoing concerns about how juries interpret forensic language.
The State used Y-STR DNA analysis, a method primarily used in forensic cases, such as sexual assaults, that works by targeting specific markers on the Y chromosome to identify male DNA within a high background of female DNA. The prosecution clarified that while the Y-STR DNA matched in five out of 23 locations, the probability of a coincidental match was roughly 1 in 189 males, making the terminology legally appropriate within Oregon standards.
In the original trial, prosecutors noted, the expert witness immediately followed the term “match” with that statistical explanation.
James remained skeptical, suggesting the terminology itself might mislead jurors. “Wouldn’t ‘partial match’ be more accurate?” he asked.
Lannet countered that the word “match” risks obscuring the statistical nature of the evidence. “Using the broad term ‘match’ dusts away the probability,” the attorney said.
Throughout the arguments, McMahon’s defense attorneys cautioned against oversimplifying complex forensic evidence for the jury, referring to the use of certain language as part of “the gatekeeping of science.”
Other justices probed the interplay between the initial deceptive interview and the second, examining whether the scope or nature of questioning might have influenced McMahon’s decision-making. Questions highlighted the broader theme of police tactics, the voluntary nature of waivers and how courts weigh evidence obtained after procedural missteps. Several justices repeatedly asked the prosecution to clarify their interpretation of past cases and the reasoning behind their evidentiary choices.
To all such inquiries, the prosecution maintained that whatever “psychological impacts” the previous interview might have had cannot be considered, referencing past U.S. Supreme Court cases. This includes Oregon v. Elstad, where the Court ruled that a voluntary statement given after proper Miranda warnings can still be admissible even if the suspect earlier made an unwarned statement, provided the later waiver was voluntary. The State invoked it to argue the second interview created a valid “clean slate.”
While understanding the rationale for invoking said case, James drew a distinction between state-level Oregon courts and federal courts. Noting that while not irrelevant, the Court could not overly use federal precedent in state decision making since the case was a matter of state Miranda law not federal.
Following the oral arguments, students had the rare opportunity to ask questions directly of the justices. Topics ranged from procedural clarifications to lighter curiosities, including whether the justices ever ate scones while making decisions — a tradition recounted by former court clerks from LC. The justices also offered practical advice for law students: focus on your weaknesses, engage respectfully with opposing arguments and consider clerkships even if they seem out of reach. They encouraged students to take full advantage of opportunities at LC, noting that many alums had successfully clerked in Oregon courts.
The event highlighted the importance of civil discourse and critical thinking in legal education. Students witnessed not only how legal arguments unfold at the appellate level, but also how judges weigh evidence, question assumptions and interpret the law in real time. By observing the exchange between defense and prosecution, students gained insight into the nuances of legal strategy, the weight of precedent and the human element of courtroom proceedings.
About the Author
