Searn Lynch was fired from the Oxford Police Department in November after being charged with "doctor shopping" for prescription pain medicine.
Court records show he was arrested Nov. 19 on charges alleging that he got prescriptions from at least 17 doctors. He was released on $5,000 bond Nov. 20, the day he was fired.
Lynch's lawyer said in a filing Tuesday that he wants to delay the March 11 trial as he is "attempting to negotiate a resolution" to the case.
The trial is scheduled to take place in U.S. District Court in Oxford.