Another twist in the case of the conflicting causes of death for Amanda L. Wienckowski is expected to be revealed this afternoon, further challenging an Erie County medical examiner’s autopsy finding that she died of an accidental drug overdose.

Relatives of Wienckowski – a Kenmore native whose body was found naked, upside down and frozen four years ago in a garbage tote outside an East Side church – say that new medical evidence will prove that the level of opiates in the 20-year-old woman’s system was not enough to cause her death. This, they say, bolsters their contention that she was murdered.

“We know for a fact that the amount of opiates in Amanda’s blood [was] not enough to even impair her,” a family member said of the newest findings.

The findings will be released at 2 p.m. during a special meeting of the Buffalo Common Council’s Legislation Committee. Ellicott Council Member Darius G. Pridgen, committee chairman, had requested that the county’s chief medical examiner be present to explain her conclusions in the Wienckowski autopsy.

However, Chief Medical Examiner Dianne R. Vertes, one of four county pathologists to sign off on the autopsy determination of an opiate overdose, will not be present for the committee meeting, according to Pridgen.

The Council’s staff, Pridgen said, was notified that it will instead receive a written response from the medical examiner.

Pridgen said it troubles him that a second autopsy’s results contradict the county’s findings. Dr. Silvia O. Comparini, a West Coast pathologist hired by the family of Wienckowski, previously determined that the young woman was strangled.

“We were asking for the medical examiner to come and explain the forensic findings in the death of Amanda,” Pridgen said. “I refuse to go away or let this go away until I am no longer the legislative representative for the Ellicott District.”

Wienckowski’s body was found in the Ellicott District outside a church at Clinton and Spring streets on the morning of Jan. 9, 2009, several weeks after she had been reported missing. The trash tote was across the street from the home of Antoine J. Garner, the last known person to have seen her alive.

According to authorities, Garner said she visited with him on the evening of Dec. 5, 2008, for a paid sexual encounter and then left his residence.

The woman’s relatives contend that Garner killed Wienckowski and that he has changed his story three times. Police have described Garner as a person of interest in the investigation, but he has not been charged in the woman’s death.

Garner is currently facing charges of choking and beating a woman in June 2011. He was also charged last fall with a home invasion in Clarence; that case is also pending.

In addition, Garner is in the midst of court proceedings against him in the City of Tonawanda for allegedly threatening Leslie L. Brill, Wienckowski’s mother.

Erie County Legislature Chairwoman Betty Jean Grant, D-Buffalo, is expected to be present at this afternoon’s meeting.

“I’m going to the meeting because of the circumstances of how Amanda was found. It tells me that somebody was involved in the disposition of her body,” Grant said.

Peter Anderson, a county spokesman, said County Health Commissioner Dr. Gale R. Burstein notified Pridgen’s committee that it would be inappropriate for her or any member of her staff to attend the meeting. The Medical Examiner’s Office is part of the Health Department.

Anderson explained that the findings of any autopsy are confidential.