As for federalism, how was "the line crossed" ? If federal court review is granted to death row criminals under the 14th Amendment, why shouldn't federal court review be granted in disputed cases where the state has imposed a death sentence on an innocent?
Because the 14th Amendment was stretched for that power in and of itself. Now you're going to argue why not stretch it a little more? That's conservative....
This was a civil case, not a criminal one. The 10th Amendment is clear. I realize Republicans inherently hate that Amendment considering their auspicious party origin but are we now to take intrastate medical civil cases all the way to the Supreme Court because we disagree with the outcome?
The Rooker-Feldman doctrine is one of several abstention doctrines that federal courts follow. This one holds that federal courts should not hear claims that essentially ask the court to review the decisionmaking in a state case. The rationale is, basically, that the U.S. Supreme Court is available to review state court decisions that involve federal issues (like due process), and there is no need to turn the lower federal courts into a review system for state decisions.
Now, in the case of those in state or federal custody, Congress has enacted statutes that expressly require federal courts to hear claims that ask for state proceedings to be reviewed. In those cases, Rooker-Feldman does not apply.
As you probably know, Congress has recently been debating whether to adopt a law that would extend the review capacity of lower federal courts to include persons in Terri's circumstances. If that law passed, Rooker-Feldman would not apply, and the court would be able to review the state court proceedings for due process violations. So far, that law has not passed.
And it probably won't.