Lemon's "secular legislative purpose" enquiry, 403 U. S., at 612, has been a common, albeit seldom dispositive, element of this Court's cases, Wallace v. Jaffree, 472 U. S. 38, 75.
When the government acts with the ostensible and predominant purpose of advancing religion, it violates the central Establishment Clause value of official religious neutrality, there being no neutrality when the government's ostensible object is to take sides. Corporation of Presiding Bishop of Church of Jesus Christ of Latter-day Saints v. Amos, 483 U. S. 327, 335. A purpose to favor one faith over another, or adherence to religion generally, clashes with the "understanding ... that liberty and social stability demand a ... tolerance that respects the religious views of all citizens." Zelman v. Simmons-Harris, 536 U. S. 639, 718. Pp. 11-12.
McCreary County, Kentucky, et al., v. ACLU of Kentucky, 545 U.S. 844 (2005)
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