Lehman, 56, was accused in April 2008 of 11 misdemeanor counts of administering narcotics without a license. She pleaded not guilty.
The state Attorney General's Office's brought the charges, and Lehman's trial has been postponed at least twice.
Attorney General Jim Hood has said as many as 11 people in the facility died after they were given excessive medications.
Lehman's attorney, Ronald Michael of Booneville, says his client did nothing wrong.
Trial will be in the Lee County Justice Center with Circuit Judge Thomas Gardner presiding.
Scott Johnson and Sue Perry are special prosecutors.
Dr. Paul White, the facility's medical director, pleaded guilty last year to misdemeanor charges of aiding and abetting the practice of medicine without a license and one felony count of cyber stalking for sending threatening e-mails to people he thought caused the investigation.
White is among nine people subpoenaed to testify for the prosecution. He struck a deal with the state, agreed to cooperate and was sentenced to two years of probation.
Authorities claim the doctor let Lehman set doses and administer narcotics, then backdated the orders she had written.
The hospice's attorney, L.F. "Sandy" Sams, repeatedly has said the patients' deaths were not suspicious or premature. People in hospice care are expected to die because they are terminally ill with just months to live when they are admitted, Sams said.
In answer to a state motion, Gardner has prohibited Michael from asking witnesses whether patients suffered harm as a result of Lehman's actions. "This is not the issue before the court," he wrote April 13.
The investigation angered many people in the community, including those whose loved ones died at the hospice. The nonprofit hospice opened in 2005 as a pilot project to provide affordable care to rural areas and was intended as a model for other communities.
Others were angered by the way the investigation was handled. Hood fired two of his investigators after they were accused of telling grand jury witnesses to call the media.
Contact Patsy R. Brumfield at (662) 678-1596 or email@example.com.