Jahi is dead because her brain has no function. There is no circulation to her brain, she is brain dead. However, she is on a respirator and her heart is beating. Here's what the Schiavo spokesperson says:
Jahi McMath has been labeled a 'deceased' person. Yet she retains all the functional attributes of a living person, despite her brain injury.This includes a beating heart, circulation and respiration, the ability to metabolize nutrition and more. Jahi is a living human being.Actually, her respiration is provided by a machine, and the whole dispute is that the hospital wants to turn off the machine. The family and the meddlesome Schiavos want to move her to a long term care facility in Long Island -- on the opposite side of the country -- but first they need a physician to perform a tracheotomy and insert a feeding tube. No physician will do so, because physicians don't operate on corpses. The family is trying to get a court order to force the hospital to comply with their wishes.
Now, Jahi doesn't just have a brain injury: she does not have a brain, other than the kind you might find pickled in a jar. In this respect, she is not like Terry Schiavo was at the time of her own controversy. Terry Schiavo was allowed to die, at her husband's request, but Jahi is already dead. It is technically possible to keep almost any corpse in a state of oxygenation, with circulating blood, for an indefinite but typically quite a long time. If we accept this definition of human life, we will ultimately have millions of corpses in warehouses, attached to machines, at a cost of a couple of hundred thousand dollars a year apiece.
So what is going on in these people's minds? Before the availability of current technology, for all of human history, we defined death as the absence of a heartbeat. The new definition is compelled by the changed reality -- that we can keep the hearts of dead people beating. This wasn't really widely discussed publicly or decided democratically. If it had been, we might have a stronger consensus.
But still, I find this ridiculous. Having a beating heart and artificially supplied respiration does not give someone "all the functional attributes of a living person." A living person has a mind. That is what is valuable about us. What is most puzzling is that the people who claim otherwise generally -- and I don't know about the McMath's but this is true of the Schiavos and their allies -- base their claim in religion. Obviously the Bible, and religious tradition more broadly, don't address this question. They can't, because it was inconceivable until the last few decades.
So what is the religious source of this bizarre claim? I have some thoughts, but I'll let you ponder.