VANCOUVER - Medical opinion, the government's duty to protect children, parental rights and freedom of religion are clashing in a B.C. courtroom over the seizure of four premature babies from a group of sextuplets.

The children were taken from their home last year and given blood transfusions, contrary to the beliefs of their Jehovah's Witness parents.

They've long since returned to their parents, but the mother and father want the B.C. Supreme Court to declare the seizure unconstitutional.

Justice Donald Brenner said Friday that such applications often proceed in what is perceived as a life and death issue.

But Shane Brady, the lawyer for the parents, said the children were not in danger.

And because the parents weren't given the right to make that case in court before the children were taken away, Brady said the law allowing government to seize children should be declared unconstitutional.

"There was no medical emergency requiring blood transfusion,'' Brady told the court as he wrapped up his argument Friday.

"The children's vital signs were within the acceptable range.''

The babies were extremely premature when born just over a year ago.

Doctors suggested the two boys and two girls who remained alive should have blood transfusions, but the parents refused because their religion prevents the taking of blood.

When the babies were just a few weeks old, the government took over their care in order for doctors to perform the blood transfusions.

Lawyers for the provincial government have said that saving the lives of the babies outweighed the rights of their parents.

To confuse the issue even more, doctors and medical experts can't agree on a threshold for when these very low birth weight babies should be transfused.

"This is where the case gets quite interesting, given the wishes of the parents,'' Brenner said as Brady explained the broad range of medical opinion on the hemoglobin threshold considered for transfusion.

Medical studies presented at the hearing said the children weren't in danger of low hemoglobin levels.

In the days before the babies were seized, their hemoglobin levels were between 80 and 88 grams per litre. The studies presented to the court said levels of hemoglobin, the iron-rich protein in red blood cells, aren't low until they dip into the 70s.

"You must ask the question if this was a medical emergency,'' Brady told the chief justice. "The answer is no.''

B.C., New Brunswick, Northwest Territories and Nunavut are the only jurisdictions in Canada to allow the government to seize children without a hearing. Brady wants the court to rule that it is unconstitutional to do so.

"Before you can authorize medical treatment there must be a fair hearing,'' he stated.

Brady said the parents should be entitled to make medical choices for their children.

"How can the state possibility justify seizing children when scientific debate is deeply divided?'' he asked.

The government lawyers had argued even if death wasn't imminent, the children could be harmed physically or mentally without the treatment.

"There was no risk of cognitive delay in January, 2007,'' Brady stated. "Today there is still no evidence of cognitive delay.''

The four remaining sextuplets celebrated their first birthday last month and were in good health.