SAN FRANCISCO (CBS SF) – An attorney for the family of an Oakland teenager who was declared brain-dead says he has video proof that Jahi McMath still has brain activity, and is seeking an unprecedented court order declaring her alive.

San Francisco Attorney Chris Dolan released the first photo of McMath since massive surgical complications Thursday. On Friday he released video of Jahi moving, and told reporters that doctors at the nonprofit International Brain Research Foundation ran tests at Rutgers University, finding signs of brain function.

The video was released during a press briefing Friday where Jahi’s mother, Nailah Winkfield, said she has documented other responsive incidents, and she can differentiate between those movements and spinal reflex.

The claims come months after three doctors, including one appointed by a judge, declared McMath brain-dead, and Alameda County issued a death certificate after her recovery from a Dec. 9, 2013 tonsillectomy went horribly wrong.

Since then, Jahi’s mother has pushed for keeping her daughter’s organs functioning on life support, first at Children’s Hospital in Oakland and later at an undisclosed medical facility in New Jersey.

“This is groundbreaking, and it seems ‘mother knew best’ all along,” Dolan said in a press release.

The attorney said Jahi and her parents moved to a house in New Jersey about a month ago where the girl remains on life support.

On Thursday, Philip DeFina, chief executive and chief scientific officer of the International Brain Research Foundation, said Jahi has responded to commands many other times. In January, video surfaced which purported to show McMath having a reflex reaction when ice was rubbed on her foot.

“There is a consistency to it,” DeFina said of Dolan’s new video.

DeFina also said brain scans showed electrical activity, and other tests showed blood flowing to the brain.

David Magnus, director of the Stanford Center for Biomedical Ethics, said this is highly unlikely, “There is no evidence that patients who are brain dead can ever recover. There is no recovery from death.”

At the same time, Magnus admits, “It’s a little surprising that the body has lasted as long as it has, but there’s a lot of variation across brain-dead, deceased patients.” He said some patients can live for years on ventilators.

He is concerned for the family, telling KPIX 5, “It’s very sad that the family hasn’t been able or put in a position to move on from this and move on to really grieve for the loss of her daughter.”

Arthur Caplan, head of medical ethics at New York University’s Langone Medical Center, said he knows of no cases in medical history where a brain-death determination was later reversed. He cautioned that the data collected on Jahi has to be examined by other researchers and experts in the field before any conclusions can be made.

“Were this to be true, it would be an earth-shattering development in understanding death,” Caplan said. “They’re playing a high-stakes game.”

Magnus agrees, saying McMath’s attorney should be calling for corroboration at the upcoming hearing.

“At this point, if he’s got experts or so-called evidence to the contrary, I would think he would ask for independent verification from a court-appointed neurologist,” Magnus said. “If they believe a large number of neurologists were all incorrect in their previous diagnoses and made huge errors, I would think they would at the minimum need an independent, court-appointed, competent, qualified neurologist to verify that all the previous independent neurologists who had done an evaluation did so in error.”

Lawyers for the University of California, San Francisco Benioff Children’s Hospital said the evidence in Jahi’s case still supports the determination that she is legally dead.

“This is a sad situation where the court made the correct determination that Jahi McMath was dead,” hospital attorney Douglas Strauss stated in court papers. “There is no factual basis or legal justification for requiring those involved to endure re-litigation of that properly reached determination.”

After the December surgery, Jahi began bleeding heavily and went into cardiac arrest. She was declared brain-dead Dec. 12.

Her mother and other family members refuse to believe the girl is dead as long as her heart is beating. They went to court last winter seeking an order to prevent the hospital from removing a respirator and feeding tube.

The two sides reached an agreement allowing Jahi to be transferred if her mother assumed responsibility for further complications. She was removed from Children’s Hospital on Jan. 5, less than two days before an injunction that would have allowed the hospital to remove the equipment.

A court hearing has been scheduled for Oct. 9.

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