The struggle over the fate of Terri Schiavo appears to be drawing to a close. The 41-year-old Florida woman suffered severe brain damage as a result of a cardiac arrest in 1990 and has been in a persistent vegetative state ever since. She can breathe for herself, but has to be fed through a tube.

The struggle over the fate of Terri Schiavo appears to be drawing to a close. The 41-year-old Florida woman suffered severe brain damage as a result of a cardiac arrest in 1990 and has been in a persistent vegetative state ever since. She can breathe for herself, but has to be fed through a tube.

The parents of Ms Schiavo have been locked in a bitter legal battle with her husband and legal guardian, Michael Schiavo, over whether she ought to be allowed to die. Mr Schiavo argues that his wife has no quality of life and no prospect of recovery. But Ms Schiavo's parents distrust her husband's motives and are adamant their daughter should be kept alive. And so for seven years the two parties have fought it out in the Florida courts. The tragic case reached its nadir last weekend when the US Congress rushed through a special law allowing federal courts jurisdiction over the case. This was part of a final attempt by Ms Schiavo's parents to keep their daughter alive, after the state courts persistently found in favour of Mr Schiavo.

Now the legal process appears to have played itself out. No federal court has taken up the case. The US Supreme Court has repeatedly refused it. Ms Schiavo's feeding tube was removed over a week ago. With no judge to order it to be reinserted, she will probably die in a matter of days.

While it is impossible not to feel sympathy for what Ms Schiavo's family has been going through, there is a strong sense that her case has been hijacked. The interference in this case by the Republican-dominated Congress - and President Bush himself - was almost certainly intended to curry favour with the evangelical right, for whom Ms Schiavo has become a cause célèbre. The same is no doubt true of the significant involvement of the Florida governor and reputed presidential hopeful, Jeb Bush. The last US election demonstrated just how significant Christian conservatism is within the Republican party. The Schiavo case has to be seen through this prism.

But this politicking almost corrupted America's constitutional separation of powers between the executive and judiciary. Fortunately, the federal courts - following the lead of the Supreme Court - decided to stay out of it. But it could easily have been different. Americans, usually so jealous of their independence, came perilously close to seeing a private family dispute settled by the federal government.