First Amendment.
Cite the law that the federal judge based the order to remove the monument on.
First Amendment and sixty plus years of Supreme Court precedent.
You can't do it, because it doesn't exist,
I just did and came to the same conclusion that every judge who has reviewed this case has reached including the trial judge, three judges on the Court of Appeals, and nine Supreme Court Judges.
and in fact cannot exist because of the simple wording of the First Amendment to the Constitution.
Only an idiot would fail to understand the role of the judiciary in interpreting the Constitution and the law in general. No law can be written to cover every possible factual situation, which is why we have the judiciary to develope case law and a body of Federal commonlaw. The First Amendment, for example, prohibits government from passing laws abridging free speech and the right to peacefully assemble, without exception, yet there are dozens of judically recognized exceptions such as yelling fire in a crowded theater, inciting a riot, fighting words, harrassment, peacefully assembling on the floor of the Senate or House of Representatives, public use of profanity, and even tresspassing on to your private property for the purpose of political protest. The First Amendment also fails to define the term "religion," and since the judiciary, in your view, lacks the authority to render decisions that have the binding effect of law, a religion must mean anything I want it to mean, and thus, if a person declares their favorite perversion a religious experience, then government is powerless to pass a law preventing that person from practicing that religion. Another example lies in the Fourth Amendment, which refers to, but does not define "unreasonable searches" and "probable cause." If not for judicial interpretation and the fact that those interpretations become binding precedent and the law of the land, those terms would mean whatever the prosecution says they mean, and the protections that the Fourth Amendment is supposed to provide to the citizenry would be totally illusory.
I don't expect you to agree or even understand because you have an agenda to promote and why let 225 years of Constitutional Law and a 1000 years of jurisprudence stand in the way.
Is this a serious question? Lower courts are bound by the decisions of higher courts. The 11th Circuit decision was based on Supreme Court precedent, and the district judge was following the ruling of the 11th. It's pretty simple, really.