The trial of Dr. Sanjay Sinha of Woodstock, Georgia, was scheduled for Sept. 8.
U.S. District Judge Sul Ozerden rescheduled the trial to start Dec. 8.
Sinha, 49, is charged with one count of conspiracy charge and six counts of drug distribution.
The Sun Herald reports Sinha's attorneys are asking the court to suppress statements Sinha made to federal drug agents after his arrest. Ozerden will hear the motion on Sept. 4.
Prosecutors argue in court documents that Sinha signed an agreement March 3 to waive his right to an attorney before that interview.
An indictment alleges Sinha wrote prescriptions outside the scope of professional practice and others conspired to help him illegally distribute narcotics from 2009 until mid-February.
Monday was the deadline for Joshua James Locke to accept a plea agreement. His attorney asked for an extension. Ozerden moved the deadline to Friday.
Locke, 36, lives in Biloxi. He was indicted on one count each of conspiracy and possession with intent to distribute hydrocodone.
Co-defendant Robert Thornton II, 36, also of Biloxi, is scheduled to plead guilty.
John Mattina, 44, of Ocean Springs, has pleaded guilty to a drug distribution charge. Mattina is set for sentencing Nov. 6.
Six others were arrested on state drug charges.
Information from: The Sun Herald, http://www.sunherald.com
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