Adult entertainer Natasha Stewart, who uses the name Pebbelz Da Model, is charged with depraved-heart murder and other counts in the death of 37-year-old Karima Gordon, of Atlanta.
Prosecutors say Gordon paid Stewart $200 for a referral to the suspected injector.
Authorities say Gordon died from blood clots in her lungs days after being injected with a silicone-type substance.
Hinds County Circuit Court Judge Bill Gowan said during a hearing Friday that the defense may have to hire a new witness if the current one doesn't turn in a report early next week.
Gowan said he'll continue the trial if prosecutors need more time to prepare arguments based on the expert's findings.
Defense attorneys Kevin Camp and Jared Tomlinson told the judge that the expert had promised to get them the report, but hasn't.
Along with the charge of depraved-heart murder, a legal term for an action that demonstrates a "callous disregard for human life" and results in death, Stewart, 40, is also charged with wire fraud, conspiracy to commit murder and conspiracy to commit wire fraud. Authorities said she falsely presented the person performing the procedure as a licensed medical professional . She faces life in prison if convicted.
Tracey Lynn Garner, a floral and interior designer, is charged with giving the injections and is scheduled for trial in March. Authorities initially identified Garner as a man, Morris Garner, but her attorney said Garner, who was born male, had sex reassignment surgery. Garner too is charged in Gordon's death with depraved-heart murder and is facing life in prison.
She also is charged in the 2010 death of Marilyn Hale of Selma, Ala., who authorities say died from similar injections.
Authorities said Gordon became ill just a few hours after Garner performed the $1,500 procedure in March 2012. A friend of Gordon's who drove to the Jackson, Miss., home with her for the injections, called Garner and asked what to do and authorities said Garner recommended cough medicine. Gordon died days later at a Georgia hospital.
Garner, who was arrested in September 2012 and pleaded not guilty, is free on bond. Stewart, who was arrested Jan. 3, 2013, in Memphis, Tenn., is jailed in Hinds County.
A gag order in the case prevents their lawyers from commenting.
Black market procedures are a problem across the country as people seek out cheaper alternatives to plastic surgery. Deaths from black market buttocks injections have also been reported in Alabama, Georgia, Florida, Pennsylvania, Nevada and New York.
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