Free Exercise Clause test

if the purpose or effect of a law is to impede the observance of one or all religions or is to discriminate invidiously between religions, that law is constitutionally invalid even though the burden may be characterized as being only indirect. But if the State regulates conduct by enacting a general law within its power, the purpose and effect of which is to advance the State's secular goals, the statute is valid despite its indirect burden on religious observance unless the State may accomplish its purpose by means which do not impose such a burden.