Windslowe, 42, is charged with third-degree murder and related counts in the death of Claudia Seye Aderotimi, 20, who died of a pulmonary embolism after Windslowe gave her a butt injection during a "pumping party" at a hotel near Philadelphia International Airport.
Malice is an element of third-degree murder, which carries a maximum sentence of 20 to 40 years in state prison.
If Rudenstein is able to convince the jury that Windslowe did not act with malice, the most serious charge she could be convicted of is involuntary manslaughter, which carries a maximum sentence of 2 1/2 to five years.
"She believed what she was doing was safe . . . At the time that she was doing it, in her heart and mind, she didn't think she was putting anyone in harm's way," Rudenstein told Common Pleas Judge Rose Marie DeFino-Nastasi.
Assistant District Attorney Bridget Kirn opposed allowing Windslowe's customers to be called as witnesses. She compared that strategy to a heroin dealer arguing that he is not guilty of causing a death because he has other clients who did not die.
In rejecting Rudenstein's request, the judge said such testimony would not be "relevant" nor "probative."
Windslowe, however, will be given "great leeway if she testifies," DeFino-Nastasi said.
Rudenstein said he expected that she would testify, although he had to stop her from speaking several times during the hearing.
Windslowe, dressed in a black blouse with white dots, tight black pants and white sneakers, has been in jail awaiting trial for nearly 2 1/2 years. She is also charged with aggravated assault for administering a silicone butt injection that gravely injured a 23-year-old Philadelphia woman in February 2012.
Despite her predicament, while being escorted from the courtroom by deputy sheriffs, Windslowe smiled, waved and said, "Good day, commonwealth," to Kirn and her co-counsel, Carlos Vega.
"OK, goodbye," Vega replied.
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