A trial court erred in awarding custody of a child to its father on the basis of the father's more active participation in organized religion, ruled an Illinois appeals court. The court concluded that favoring religion in child custody hearings violates the First Amendment's nonestablishment of religion clause. The court did acknowledge that evidence of a parent's religious faith is admissible in evidence, but cannot be the basis of an award of custody. Zucco v. Garrett, 501 N.E.2d 875 (Ill. App. 1986).