The ruling Thursday by a three-judge panel of the court came in a case brought by the Freedom From Religion Foundation.
The court said the proclamations in question sometimes included biblical verses and religious themes and were effectively a government endorsement of a religion in violation of the state constitution.
The appeals judges sent the case back to a trial court to decide whether any other Colorado governor should be barred from making similar proclamations. They said they didn't consider presidential National Day of Prayer proclamations in their ruling and noted people can still pray.
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