President Donald Trump‘s former national security advisor Michael Flynn has fired the lawyers representing him in Robert Mueller‘s Russia probe, indicating a possible change in Flynn’s legal strategy. The lawyers, Rob Kelner and Steve Anthony, were instrumental in obtaining the 2017 plea deal for Flynn after it was discovered that he had lied to the FBI.

Kelner and Anthony, employees of the Covington & Burling law firm, announced in a court filing on Thursday that their client was “terminating” them, and that Flynn had already found new legal counsel. The former Trump advisor has not publicly disclosed who will be replacing Kelner and Anthony on his defense team.

Flynn has spent the last few years heavily involved in the justice system after pleading guilty to lying to federal officials. In December 2017 the former national security advisor admitted that in January of that same year he had given false information about a conversation with Russian Ambassador Sergey Kislyak. Since then Flynn has been a key witness in Mueller’s investigation into election interference by the Russians, giving at least 19 interviews to the special counsel.

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Because of the integral part which he has played in the Russia probe, Flynn has yet to be sentenced for the one count of lying to the FBI which he pleaded guilty to. Flynn’s lawyers have played important roles in keeping their client out of prison, ingratiating the former advisor with federal prosecutors in order to receive a more lenient sentence. After their investigation concluded, Mueller’s team recommended that Flynn receive no jail time for his crimes.

Flynn’s firing of his lawyers raises questions about what legal course he intends to pursue next, now that the special counsel’s investigation has ended. It is possible that the former advisor will take a more combative road, as his friends and family have suggested, diverging from his previous strategy of cooperation with prosecutors.