As part of his criminal trial at the Southern District of New York, Sam Bankman-Fried has been locked in a battle with prosecutors, who have accused the disgraced FTX founder of influencing former employees who may testify at his trial.

In a decision on Wednesday, the judge overseeing the case sided with prosecutors, ruling that Bankman-Fried must stop communicating with current or former employees of FTX and its affiliated trading firm, Alameda Research, except in the presence of lawyers. Per the prosecutors’ request, the judge added that Bankman-Fried not be allowed to use any encrypted messaging platforms, such as Signal.

The U.S. Department of Justice in December charged Bankman-Fried with eight criminal counts related to the collapse of FTX, with the FTX founder pleading not guilty at a hearing in January. As part of his bail conditions, Judge Lewis Kaplan allowed Bankman-Fried to live with his parents and maintain access to the internet, where he has remained active. A little over a week after his arraignment, Bankman-Fried started a Substack outlining his defense of FTX’s balance sheet.

According to a filing on Friday, prosecutors believe Bankman-Fried was using email and Signal to contact former employees who may serve as witnesses at his upcoming trial. This included the general counsel of FTX US, whom prosecutors called “Witness-1” and referred to Ryne Miller.

In a subsequent court filing on Monday, prosecutors included Bankman-Fried's messages to Miller as an exhibit. Over both Signal and email, Bankman-Fried wrote to Miller that he would “really love to reconnect and see if there’s a way for us to have a constructive relationship.” Bankman-Fried's lawyers referred to the messages as an “innocuous attempt to offer assistance in FTX’s bankruptcy process.”

In his ruling today, Kaplan disagreed with SBF’s lawyers’ interpretation of the outreach, writing that the message “appears to have been an effort to have both the defendant and Witness-1 sing out of the same hymn book.”

Bankman-Fried's lawyers will have a chance to appeal Kaplan's decision at a hearing scheduled for Feb. 7. It's also likely they'll appeal another recent decision by Kaplan in which he ruled that Bankman-Fried's two bond cosigners be made public. The deadline for an appeal for that ruling is also Feb. 7.

This story was originally featured on Fortune.com

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