According to the
Washington Post, Robert and Mary Schindler fear for the fate of their daughter's soul:
Attorneys for Robert and Mary Schindler argued that allowing their brain-damaged daughter to die before the federal courts can review her case would violate Congress's will and lead to the "damnation of her soul" because it would conflict with her religious beliefs. Her husband's legal team countered that Congress trampled the Constitution by bending to "popular clamor" and ignoring a long string of judicial rulings in what they called one of the most extensively litigated cases in Florida history.
I couldn't figure this one out, even though I'm a recovering Catholic. How could she be held responsible for the actions of others. But then it hit me: they fear that their daughter will be damned because they know that her husband is carrying out her wishes, and thus it's assisted suicide, and suicides go to hell. By even making this argument, they give the game away.