WNBA star Brittney Griner was back in a Russian court Tuesday for her drug trial while the U.S. attempts to have her released from the country.

Driving the news: Defense experts argued that the examination of the substance inside the vape cartridges Griner had did not comply with Russian law, CNN reports.

Background: Griner, 31, pleaded guilty last month to the drug charges, but said she had "no intent" of bringing the vape cartridges to Russia.

The big picture: The U.S. maintains that Griner, a two-time Olympic gold medalist who plays in Russia during the WNBA offseason, is wrongfully being detained.

What's next: The trial is scheduled to resume Thursday for closing statements.