A Maryland couple pleaded guilty for the second time in relation to federal charges that allege they attempted to sell secret information about United States submarine nuclear propulsion systems to a foreign nation.

The pleas were made on Tuesday after the suspects, identified as Jonathan and Diana Toebbe, previously pleaded guilty in February. That case, however, was thrown out by a judge last month after deciding that the sentences called for were too low.

Selling Classified US Data

The two individuals, from Annapolis, Maryland, seemed to neighbors and co-workers as a common suburban couple before authorities arrested them last October. Their crimes include allegedly scheming to sell secrets about Virginia-class nuclear submarines to another country,

When Toebbe made his plea, he conceded that he sent a package to a foreign government and listed a return address in Pittsburgh. It contained a sample of restricted data and instructions for establishing relationship to purchase additional restricted data.

The suspect added that he began corresponding with someone that he thought was a representative of the foreign government but was in fact an undercover FBI agent. The latter, on June 8, 2021, sent $10,000 in cryptocurrency to Toebbe as a "good faith" payment, as per ABC News.

Prosecutors said that a few weeks after that, the couple traveled to a location in West Virginia where Diana was acting as a lookout, Toebbe placed an SD card concealed within half a peanut butter sandwich at a pre-arranged "dead drop" location.

The undercover agent, after retrieving the SD card, sent Toebbe an additional $20,000 in cryptocurrency for payment. The suspect, in return, emailed the uncover agent a decryption key to access the information stored within the SD card.

According to the Associated Press, the previous sentencing range that Toebbe's lawyers agreed to included potential imprisonment of between 12 and 17 years. On Tuesday, prosecutors said that such a sentence would be one of the most significant imposed in modern times under the Atomic Energy Act of 1954.

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Undercover FBI Agent

Now, the latest plea agreement entered before U.S. Magistrate Judge Robert Trumble includes a maximum sentence of life in prison and a $100,000 fine. However, prosecutors are requesting a sentence for Diana at the lowest end of the guideline range.

If the court decides not to accept the latest agreement, the two suspects would once again have the right to withdraw their guilty pleas. Prosecutors allege that 43-year-old Toebbe took advantage of his access to top-secret government information.

His partner, 46-year-old Diana, was a teacher at a private school in Maryland at the time that the couple was arrested last October. The SD cards did not contain information that was classified as top secret or secret.

The case raised questions about why a couple with a comfortable life in a middle-class neighborhood would risk their lives in an attempt to sell classified information to a foreign nation. A lawyer for Diana, in court, referred to personal difficulties with which his client said she had to struggle with, without elaborating further, the New York Times reported.

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