The 14th Amendment to the U.S. Constitution, section 1 of which reads:
Section. 1. All persons born or naturalized in the United States and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside. No State shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any State deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws.
"Terri's Law" granted the US federal courts power to review decisions taken in this case by the Florida state courts. The most frequent use of the 14th amendment, is by death row inmates who have been sentenced for capital crimes in state courts, and appeal to the federal courts, claiming the state process was so deficient as to deprive them of "life" without "due process of law".
Terri's Law is, without question, constitutional.
I'm not sure the 14th Amendment applies in this case, although I understand the arguments on these grounds. I could be wrong, of course, about whether or not it's applicable. As mentioned to another poster, I'll be interested to see how the courts rule should the case move up the federal court food chain. The lawyers for the parents are likely to use this clause in their arguments.
If you adjudicate as such, why all the wasted motion going to the District Court?
Florida has a law permitting starvation and dehydration.