Because the school forbade all religious instruction under its policy, the court ruled that it was not engaging in unconstitutional viewpoint discrimination.

But in Lamb's Chapel, the Court left open the question of whether such a concern could also justify viewpoint discrimination.

The Court ruled that it could not, and gave four reasons for distinguishing content-based discrimination from viewpoint discrimination on this score.

They were considered by the American Civil Liberties Union to be "viewpoint discrimination", thus unconstitutional.

They showed pretty conclusively that what was going on was viewpoint discrimination, and that's not allowed.

For a public station to say that would be "viewpoint discrimination," Mr. Marks replied.

In its practical operation, moreover, the ordinance goes even beyond mere content discrimination, to actual viewpoint discrimination.

As a result, the decision was viewpoint discrimination and could not withstand scrutiny.

However, if the government is basing some judgment of "quality" on the views, then only "invidious viewpoint discrimination" is barred.

To exclude this activity while permitting others would be unconstitutional viewpoint discrimination, Justice Thomas said for the majority.