The Colorado Court of Appeals has unanimously held a series of day-of-prayer proclamations, issued by the governor of the state in recent years, to be unconstitutional. The case was decided under the state constitution, rather than the Establishment Clause of America's federal constitution, though the test used was one that is familar from federal litigation in the US, i.e. the Lemon test:
1. The governmental action must have a secular purpose.
2. The principal or primary effect must be one that neither advances nor inhibits religion. AND
3. It must not foster an excessive government entanglement with religion.
You'd think cases like this would be straightforward - what on earth is a government in a secular, pluralist society doing enjoining its citizens to engage in a religious activity such as prayer, and how can this not violate any constitutional provisions that separate government from religion? - but it proves difficult in practice.
This is an important victory for the Freedom from Religion Foundation, and hopefully it will stick. I'm not sure whether any further appeal is possible - since the matter involves the interpretation of a state constitution, I don't see how the US Supreme Court would or could deal with it (in the US, state supreme courts are the highest interpreters of state constitutions). However, I'm not au fait with the judicial structure in Colorado. Is there any way to get a Court of Appeals judgment reviewed or overturned within the state system there, does anyone know?