WASHINGTON — The Supreme Court on Thursday For a convicted drug trafficker from California, she challenged evidence admitted at trial that suggested she knew about thousands of dollars’ worth of methamphetamine found in her car.
The 6-3 vote ruling means that Delilah Guadalupe Diaz’s conviction will be upheld.
Diaz claims he was a “blind” courier, meaning he was transporting drugs unknowingly.
A U.S. citizen living in California, she was stopped by Border Patrol agents while attempting to enter the U.S. from Mexico at the San Ysidro Port of Entry in August 2020.
The search uncovered 55 pounds of methamphetamine with a retail value of $368,550.
Diaz, who was sentenced to seven years in prison, said her boyfriend had lent her his car when she was returning to the United States from a trip to Mexico.
The case focused on rules of evidence that were amended after John Hinckley Jr. was acquitted by reason of insanity in the 1981 assassination attempt on President Ronald Reagan. Congress changed the rules to exclude expert testimony about a defendant’s mental condition.
The rule states that “an expert witness may not opine on whether the defendant had a mental condition or symptom that constitutes an element of the offense or defense charged.”
At Diaz’s trial, Homeland Security agents testified that drug cartels typically do not allow large quantities of drugs to be transported by so-called blind couriers, who do not know the load of the goods.
Diaz’s lawyers unsuccessfully tried to exclude the testimony, arguing it was “substantially equivalent” to telling jurors that his client knew about drugs.
Justice Clarence Thomas wrote in his ruling Thursday that Flood “expressed no opinion as to whether the petitioner himself was in a particular mental state” and was merely talking about what would typically happen in similar situations, and therefore no rules of evidence were violated.
He added that the jury was “fully aware” that blind drug traffickers exist and that Diaz may have been one of them, but ultimately concluded that the evidence “pointed to a different conclusion, that Diaz knowingly transported the drugs.”
Conservative Justice Neil Gorsuch wrote a dissenting opinion, joined by the court’s two liberal justices, Sonia Sotomayor and Elena Kagan.
He sharply criticized the ruling, saying it gave prosecutors a “powerful new tool” by allowing them to call witnesses who could incriminate a defendant as part of expert testimony.
“Prosecutors can now call on the stand an expert — who apparently has the convenient ability to read minds — to talk about what ‘most’ people like the defendant think when they commit legally prohibited acts,” he wrote.
During arguments in the case in March, lawyers representing the Justice Department told the judges that prosecutors do not need to present the kind of evidence presented in Diaz’s case to secure a conviction.
