The Lemon test (in its original form):

A challenged government program is constitutional if it satisfies all three parts of the 3-part test:

(1) it must have a secular legislative purpose (that is not a sham); and

(2) a primary effect that neither advances nor inhibits religion; and

(3) it cannot create an excessive government entanglement with religion (with a religious entity).


(1) In applying the Lemon test, there must be a secular purpose, but the secular purpose does not have to be the only purpose or the primary purpose. It does, however, have to be an actual purpose rather than a sham. A sham purpose would be a fictitious purpose that the government has fabricated to avoid its action being invalidated on Establishment Clause grounds.

(2) The effect prong is the most difficult to apply. The government is unlikely to be viewed as advancing religion if it distributes a neutral benefit (such as free bus transportation or school lunches) that aids religious schools only indirectly and is distributed to a broad range of beneficiaries that include all schoolchildren (whether they attend public or private schools and whether the private schools are religious or nonreligious schools). However, direct aid to parochial schools that can be used to support its religious mission would violate the effect prong.

(3) Excessive entanglement involves the government working together with a religious entity. Certain forms of interaction are not constitutionally problematic. For example, excessive entanglement does not exist where there is only administrative cooperation (filling out forms such as the attendance forms in Zorach, providing financial information, occasional inspections, etc.) between the government and a religion or a religious entity like a parochial school. On the other hand, pervasive monitoring of the teachers at a parochial school by the government would be excessive entanglement. In addition, if the government delegates governmental power to a religious entity, the relationship will be viewed as creating excessive entanglement.