(CNN) The defense team of spying suspect Maria Butina walked into the courtroom Monday riding high on a concession from prosecutors that they misunderstood her text message jokes about sex. Less than an hour later, however, the defense lawyers left the hearing under a gag order and with the 29-year-old Russian heading back to a Virginia jail.

Butina has pleaded not guilty to two criminal charges, of conspiracy and acting as an unregistered foreign agent in the US. She is accused of working for Russian politician Alexander Torshin to infiltrate Republican politics and, specifically, the National Prayer Breakfast and the National Rifle Association so she could advance Russia's interests. She's been in jail since her arrest in July. Torshin is not charged. No trial date is set.

Federal Judge Tanya Chutkan ordered Monday that Butina would stay in jail until her trial because she is a flight risk.

"I cannot envision a scenario where it's not possible," Chutkan said, for Butina to walk out of jail, get in a car with diplomatic plates and take a flight out of the country if she were to be released before her trial. "There's a very real risk of flight."

The hearing failed to offer any boost to Butina, even with the Justice Department's admission of error over the weekend.

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