I find this very sad She was a loving and devoted mother of three children under the age of nine who was on her way to an alcohol rehabilitation facility to seek treatment," Betsy Gotbaum, the victim's stepmother-in-law, said in a statement.
Carol Gotbaum "appears to have been manhandled by the Phoenix Police Department," said Gotbaum, New York City's public advocate. "She cried out for help at the airport, but her pleas appear to have been met by mistreatment."
"We are not jumping to any conclusions, but the circumstances surrounding Carol's death appear to be unusual enough to raise serious questions and warrant a thorough investigation," Betsy Gotbaum said.
Police spokesman Sgt. Andy Hill said officers checked on Gotbaum regularly while she was detained. During one of the checks, officers found Gotbaum unconscious with her hands "pressed against her neck area," Hill said.
In a statement released later Monday, Hill said Gotbaum had been shackled to a bench as well as being handcuffed. The shackle's chain ran from an eyehook and the other was connected to the chain on Gotbaum's handcuffs.
Hill said officers followed established policy while detaining Carol Gotbaum. He added that police procedures for arresting someone at the airport haven't changed since the Sept. 11, 2001 terrorist attacks.
"Everything, so far that we know, is according to policy," Hill said.
Manning, who was hired by Gotbaum's family to monitor the police investigation, said it doesn't seem possible she could have killed herself.
"It doesn't make any sense," he said. "She was handcuffed behind her back and shackled to a table. It doesn't make sense that she could have physically managed to strangle herself."
Manning, a high-profile lawyer who represented the government against failed savings and loan executive Charles Keating, has previously won settlements against Maricopa County Sheriff Joe Arpaio in wrongful-death lawsuits.
He said the family hasn't decided whether it should file a lawsuit against Phoenix police.
"We're not going to jump to any conclusions without any evidence," he said. "We want to see what the autopsy reveals. We want to see what exactly happened to her."