The lower court ruled that religious symbols present at the secular, public ceremony amounted to a coercive imposition of religion onto the children of the Wisconsin school.
The Supreme Court recently ruled that sectarian prayers to start town council meetings are allowed, as those official prayers do not force citizens to pray and do not amount to establishing religion. This decision would seem to indicate that the court thinks there's more of a need to serrate church and state when it comes to children.
According to Lyle Denniston of Scotusblog.com, this is "a fairly clear signal" from the Supreme Court that depite "its new willingness to allow more religion in public life probably does not mean it will allow children to be exposed to more such symbolism when they don't have a choice about it."
Justice Anton Scalia, who holds a very strict view of what counts as religious "coercion," objected to the court's decision. He said the court has inverted the purpose of the First Amendment of the Constitution, allowing those who don't like religion to banish it from public space.
Scalia, joined by Justice Clarence Thomas, writes:
Some there are -- many, perhaps -- who are offended by public displays of religion. Religion, they believe, is a personal matter; if it must be given external manifestation, that should not occur in public places where others may be offended. I can understand that attitude: It parallels my own toward the playing in public of rock music or Stravinsky. And I too am especially annoyed when the intrusion upon my inner peace occurs while I am part of a captive audience, as on a municipal bus or in the waiting room of a public agency.The conservative justices' comparison would seem to reduce religion to a matter of aesthetic preference. This is consistent with other arguments from conservative legal theorists. The conservative point-of-view seems to be that those who insist on the importance of separating church and state simply overestimate the importance of religion and the power of religious symbols.
My own aversion cannot be imposed by law because of the First Amendment . . . Certain of this Court's cases, however, have allowed the aversion to religious displays to be enforced directly through the First Amendment, at least in public facilities and with respect to public ceremonies -- this despite the fact that the First Amendment explicitly favors religion and is, so to speak, agnostic about music.