By Becky Branford BBC News

Terri Schiavo's parents kept up their fight to keep their daughter alive right until she breathed her last breath on Thursday.

But judgement after judgement over seven years supported her husband - and legal guardian - Michael, who said his wife would not have wanted to be kept alive artificially.

Public opinion may have swayed legislators

Mrs Schiavo's feeding tube was removed on 18 March in accordance with a ruling by a Florida appeals court after a protracted battle which included an intervention by state Governor Jeb Bush.

She died 13 days later despite a number of last-ditch efforts by her parents, Bob and Mary Schindler, to have her feeding tube re-inserted.

The case had resonance all the way to the top.

As time was running out for the Schindlers, President George W Bush signed a law allowing a federal court to review the case and consider again whether doctors should be obliged to keep Mrs Schiavo alive.

It was the second time new legislation had been introduced to influence events in this particular case.

The first, "Terri's Law", was passed by Florida's legislature in October 2003 and allowed Governor Jeb Bush to order doctors to replace Mrs Schiavo's feeding tube.

That law was struck down as unconstitutional by the state's Supreme Court in September 2004.

TV impact

The unusual intervention by legislators caused alarm in many quarters.

Individual states such as Florida - as well as US as a whole - have constitutions that enshrine a separation of powers between the executive, legislative and judicial branches of government.

Video of Terri Schiavo has been played repeatedly on TV networks

In general, legislatures pass laws and courts interpret them in individual cases.

But in this case, critics say, lawmakers in both houses of Congress allowed themselves to be swayed by an emotional argument and repeated broadcasts of a video showing Mrs Schiavo apparently awake and alert, even though many doctors had said she had no consciousness.

Democratic congressmen from Florida accused legislators of trampling on the judgements of local judges and doctors involved in the case and taking on the role of "judge and jury".

Congresswoman Debbie Wasserman Schultz, a Florida Democrat, told the BBC legislators had no place getting involved in a family matter, either in Florida or in Washington.

"It was inappropriate and outrageous then, and it remains inappropriate for the United States Congress or any legislative body to insert itself into a gut-wrenching, angst-ridden tragedy that should be between family members," she said.

Political undercurrents

Some analysts said that political considerations lie not far beneath the surface of events.

These people in Congress are walking all over my personal and private life Michael Schiavo, husband

"This is the kind of legal-political battle we get in the United States because of the role that the Supreme Court plays in setting policy," Gregory Katz, London-based correspondent for the Houston Chronicle in Texas, told the BBC.

"There are very important legal issues at stake in terms of the right to die and the obligations that families and doctors have."

He said the case became important politically because the Republican Party and President Bush appealed to their conservative religious base in their attempt to keep Mrs Schiavo alive.

Mrs Schiavo's husband Michael was also angry that the case was taken up by Congress.

"These people in Congress are walking all over my personal and private life," he said.

"I'm telling you, United States citizens, you had better start speaking up because these people are going to invade your personal and private affairs and make a mockery of this."

'Starvation'

But others argue that it is quite right that Congress should become involved in matters of ethical principle.

David Gibbs, a lawyer representing Terri Schiavo's mother, said he was delighted with the role legislators had played in trying to prevent a woman "being starved and dehydrated to death".

"What the United States Congress and what the president of the United States said is, 'This is not right,'" he told the BBC.

"And we as a nation, under our constitution, and under our history, have always been the protectors and defenders of life, and in this situation it appears that our law has not adequately protected the life of Terri Schiavo."