Thirty-two-year-old Rebecca Zahau was found dead on July 13, 2011. Her naked body was discovered bound and gagged, hanging from a balcony at her boyfriend’s California mansion. Her boyfriend’s brother, Adam Shacknai, who was staying in a guest house on the property, discovered the young woman and says he attempted CPR as he called 911.

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After a seven-week investigation, police concluded that Zahau died by suicide, distraught over serious injuries, including brain damage, that her boyfriend’s son suffered while in her care just days prior.

Rebecca’s family, however, insists she was murdered. They say there is no way she would have taken her own life, so they exhumed her body three months after she was buried to have a second autopsy performed, in an effort to prove their claim.

WATCH: Rebecca Zahau’s Family Shares Details From The Trial For The First Time Since Adam Shacknai Found Responsible For Her Death

Forensic pathologist Dr. Cyril Wecht, who performed Zahau’s second autopsy, shares why he believes the investigation into Zahau’s death should be re-opened. What does he say he learned that makes him believe the young woman did not die by suicide?

Adam Shacknai was recently found civilly liable for Zahau’s death. He maintains that he is innocent of any wrongdoing and did not kill Rebecca Zahau.

This episode airs Tuesday. Watch more here.

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