The court interpreted a provision of the Federal Rules of Evidence regarding the admissibility of expert witness testimony.

[1] In August 2020, Delilah Guadalupe Diaz was returning home to California from a trip to Mexico.

Upon further inspection, agents found nearly 28 kilograms of methamphetamine hidden in the car's door panels.

At trial, the prosecution called Andrew Flood, a Homeland Security agent, as an expert on drug-trafficking organizations.

The Court ruled that Flood's statements did not constitute an "explicit opinion" on the defendant's state of mind.

On March 3, the Ninth Circuit denied Diaz's petition for rehearing en banc.