A case that was once an undercard during the Russia investigation has turned into the main event in its aftermath—and an apparent battle over the fallout from the Mueller Report.

Federal prosecutors this week begin the trial of Bijan Kian, Michael Flynn’s former business partner, on charges that he illegally lobbied on behalf of the Turkish government. But President Trump’s former national security adviser and the Russia investigation have overshadowed the trial, as the lobbying case turns into a proxy battle over whether Flynn will conclude his role in the Russia investigation as the government’s penitent cooperator with a probation sentence or a defiant MAGA martyr risking jail time.

Flynn, chastened and a model cooperator during Special Counsel Robert Mueller’s tenure, now appears to feel the wind at his back and has turned combative since the Mueller Report was published, threatening to upend the case against Kian. And prosecutors who once praised Flynn’s cooperation now appear to be playing hardball with their former star witness, putting a question mark over the lenient sentence they had advocated for him.