Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof...
– United States Constitution, 1st Amendment.
The First Amendment has two complementary objectives barring government preference of a religion as well as protecting the individual's right to practice a particular religion without government interference. As James Skillen notes, every argument for fundamental education reform encounters the claim that an open pluralistic system violates "the first amendment's establishment clause because public monies will end up in the hands of religious schools." 
In reality, choice places funds in the hands of parents who elect either public or private, religious or non-religious schools. In Detroit, most parents who select private schools elect sectarian ones primarily because they offer strong leadership, educational achievement and safety and availability. The school's religious mission is not the primary selection factor.
Single common public school systems such as Detroit's Public System owe much of their philosophy to Thomas Jefferson, Horace Mann, and other educational reformers. Jefferson believed that rational empiricism and enlightened moralism should be substituted for explicitly Christian doctrines which at the time were guiding many families, schools, and churches.  The Jeffersonian approach, a secularized form of Protestantism, became a major tenet of faith of school reformers as the United States moved from a system of private education to public education.
Educational reformers led by people like Horace Mann held a hidden agenda which included a diverse range of goals which were to be achieved by politicizing the educational system, encouraging the adoption of compulsory public education, and shifting responsibility for education from the family to the state.  From the 1840's through the next 100 years the common public school movement sought to institutionalize a system of government-established, government-funded, and government-run schools acceptable to the majority.  This trend was accelerated by the influx of largely Catholic immigrants to Boston and New York City. "When Catholics began to appeal for public support of their schools on the same basis" as Protestant schools, there was a reaction. 
The largely Protestant majority in each city reacted to the pluralizing threat by making the argument that their own schools were common and "non-sectarian" but that Catholic schools were parochial and "sectarian". They engineered the circumstances politically to give public backing and funding to the so-called "nonsectarian common schools." 
Lower income groups, in both poor and rural areas, fought compulsory schooling as a limitation of parental rights. The Irish boycotted the public schools which displaced Catholic private educational institutions. 
Public schools reflecting the evolving distinction between church and state saw the removal of religious instruction and became more secular in character.  Consistent with their agenda, uniformity of thought was encouraged by school reformers. For instance, Mann, an acknowledged leader in the one common school movement, accepted racial segregation in education and admonished educators who spoke out publicly on that issue.  Democracy legitimized incursions of the state into family affairs based on the utilitarian view that such incursions reflected majority rule. The rights of the family, particularly on religion, were to be sacrificed for the good of the community.  Such a single common system which implicitly and explicitly promotes values inconsistent with the United States', Michigan's, and Detroit's pluralism cannot be intelligently squared with the First Amendment's goal of protecting the individual's right to practice a particular religion, free from governmental interference. In essence, the Jeffersonian dogma as it evolved discriminates in favor of one dogma at the expense of literally hundreds of opposing dogmas.
Moreover, many special interest lobbyists critical of choice are unwilling to accept the premise that the government should be simply neutral on matters of religion. They go further and throw their "weight on the side of those who believe that our society as a whole should be a purely secular one." To the contrary, we believe, consistent with the diversity of views in Detroit and beyond, "nothing in the first amendment or in the cases interpreting it requires such an extreme approach"... (Justice William Rehnquist, U.S. Supreme Court). 
On the other hand, by the 1930's and 1940's, the ruling Jeffersonian hegemony (modified by the religious secular distinction and John Dewey's pragmatism) with its discrimination against non-government schools became the unquestioned starting point for citizens and justices alike. 
While a review of the entire historical and constitutional record is beyond the scope of our book, it is important to look at a few relatively recent cases.
In Board of Education v. Allen, 392 U.S. 236 (1968), the United States Supreme Court held that a state of New York law requiring local public school authorities to lend textbooks free of charge to all students in grades seven through twelve including private school student was not in conflict with either the First Amendment or 14th Amendment to the U.S. Constitution. The court looked at earlier cases and said the test is whether the purpose and the primary effect of the statute is to advance or inhibit religion. Here, the statute authorized the loan of secular books. Accordingly, it did not advance or inhibit religion. Therefore, the court found the provision of books acceptable.
Another significant case is Lemon v. Kurtzman, 403 U.S. 602, (1971). The court was asked to review a Pennsylvania and a Rhode Island statute providing state assistance to church-related elementary and secondary schools. Pennsylvania provided financial support to non-public schools by way of reimbursement of instructional cost related to specified secular subjects. Rhode Island paid a 15% salary supplement to non-public elementary school teachers. In Lemon, the court stated a three part test to determine whether a program violates the establishment clause of the lst amendment:
The statute must advance a secular purpose.
Its principal or primary effect must be one that neither advances nor inhibits religion.
It must not foster "an excessive government entanglement with religion."
The court found that both programs had a secular legislative purpose and did not advance or have the primary intent of advancing religion. However the court did conclude that the programs involved excessive entanglements between government and religion.
On the other hand in Tilton v. Richardson, 403 U.S. G72, (1971), the Supreme Court upheld Federal construction grants to religious institutions for buildings used exclusively for secular purposes. The court dismissed the claim that every form of financial aid to a church-related activity violates the religion clause. Instead, it asked, does the legislative program have the principal or primary effect of advancing a religion? The court found that grants to colleges and universities did not have the primary effect of advancing religion.
Turning to the excessive entanglements questions, the court found significant differences between church-related elementary and secondary schools and church-related universities and colleges. College students, it is claimed, are "less impressionable and less susceptible to religious indoctrination." Consequently, the court held that while the four institutions in question were governed by Catholic religious orders and both the faculty and student bodies at each were predominantly Catholic, their mission was a secular one: provide students with a higher education. Accordingly, the court found the entanglement between church and state insufficient to bar government assistance.
In Mueller v. Allen, 103 S. Ct. 3062 (1983), the Supreme Court upheld a Minnesota program which allows a deduction against income for state income tax purposes. Tuition, textbooks and transportation expenses are deductible for both secondary and elementary schools, either private (including sectarian) or public. The court held that the education had a secular purpose of "ensuring that the state citizenry is well educated." Moreover, the court held that the state had a strong public interest in ensuring the survival of both religious and non-religious private schools because they:
Relieve the public schools of educating a certain percentage of the state's population.
Provide competition to public schools. 
Moreover, the court found that the primary effect of the Minnesota program was not the advancement of religion.
Two other cases are of interest. In Bowen v. Kendrick, 108 S.Ct. 25(2 (1985), the Supreme Court allowed Federal monies to be used for a church-run social welfare program. Additionally, the Supreme Court, in Witters v. Washington Dept. of Services for the Blind 474 U.S. 481 (1956), held that the state may use rehabilitation funds for a blind person's seminary training.
Based on the foregoing cases, a system of choice, financed through vouchers or tax credits, would not violate the First Amendment, would increase the supply of good schools, reduce cost thereby reducing financial pressure on Michigan's overburdened taxpayers, as well as increase the educational performance of students from poor and low-income and middle-income families, and ensure diversity and pluralism.
First, a voucher or tax credit system advances a secular purpose. The principal objective of tax credits or vouchers is the use of private schools to promote public values.
Competition improves educational achievement at lower cost. As Sugarman points out, "there is reason to fear that choice limited to public schools will shield such schools from the competitive pressures needed to force their own improvement."  Without private competition, lousy public schools will not be allowed to go bankrupt, poor teachers will be allowed to keep their jobs.
Values such as pluralism and diversity are likely to be encouraged. The single common public school system fails to reflect tolerance of differences. Instead, a single ideological agenda is encouraged. In our view, "government should treat all its citizens evenhandedly and without discrimination. There is no question that justice demands it."  The requisite evenhandedness and non-discrimination cannot be achieved under our present educational system.
In many urban areas, private schools are the only practical source of racially integrated education for minority children. 
Choice improves the economic prospects of minorities without coercion. As mentioned previously, the achievement gap between black and white students narrows considerably in Catholic and other private schools while in public schools this gap widens. This is extremely important when one considers that at least one third of black Americans subsist below the poverty line.
In light of these secular purposes which are advanced by choice, it seems clear that the first prong of the Lemon establishment of religion test is met.
Second, neither the principal purpose nor the primary effect of choice will be to advance religion. This view is strengthened by virtue of the fact that the funds go to parents who select a school, public or private. Consistent with Mueller, a system of tax credits or vouchers made available to the parent, irrespective of whether the benefit is used at a public or private school, is no different from other government entitlement programs such as social security or rehabilitation funding. To benefit from social security, the recipient is not limited to non-religious or secular uses of funds, as the purpose of such a program is to supplement retirement income. Similarly, a system of open choice has the primary purpose of improving educational outcomes by providing minimum education income.
Turning to the third issue, excessive entanglements, a market system of education which provides funds to parents of school children who expend the funds at private or public schools does not lead to excessive entanglements, consistent with Tilton. In Tilton, the Supreme Court held that a system of grants to church-related universities passed constitutional muster. Part of that decision, however, was premised on the distinction between impressionable school children and less impressionable college students. The court found the level of entanglements insufficient where the mission of the institution was a secular one. In our view, this distinction between elementary, secondary and university education is tenuous at best. Moreover, the evidence in our survey suggests that the primary reason Detroit area parents send their children to Catholic and Lutheran Schools is very much like the reason college students go to church-related universities – to get a good education. The majority of students at Catholic schools in Detroit are non-Catholic and come from non-Catholic homes. Neither students nor the parents are required to convert. Accordingly, a publicly-financed program of choice is consistent with Lemon as explicated by Tilton.
In sum, a market-based system of individual choice advances public values and does not have the primary effect of advancing religion, nor does it involve excessive government entanglements with religion. Accordingly, such a plan should pass constitutional muster, especially in light of recent changes in the makeup of the Supreme Court. Led by Justice Sandra Day O'Connor, the court seems more willing to allow government accommodation of religious beliefs.  Moreover, such a system has the advantage of preventing the educational staff from attempting to mold all students to the view of the dominant group while preventing the emergence of individual values, likes, desires, and purposes. A market-based system of choice neutrally allows the individual to flourish within a pluralistic and diverse culture. Parents have the opportunity to choose the values and beliefs to which their children are exposed. Competition and choice encourage freedom of expression. Public school monopolies suppress it.
As Gwartney and Wagner note in their important book, Public Choice and Constitutional Economics, the task of government consistent with the Constitution is to promote the security of individual rights and provide those services that people cannot provide for themselves. Accordingly, in a system based on mutual agreement, behavior (by government) that oppresses some for the benefit of others is pathological.  Maintenance of public school monopolies in Detroit and beyond allows the poor to be oppressed for the benefit of the bureaucracy. A market-based system of education ends this oppression. Choice is not only constitutional; it promotes individual rights as well.
Moreover, tax credits and vouchers provide aid to parents without state discrimination. Where government treats competing activities that are secular the same way it treats religious activities, it will create neither incentives nor disincentives to engage in religious activities.  In our view, tax credits and vouchers move us towards the goal of neutrality. Accordingly, such a program should be embraced.
Any discussion of educational choice in Michigan would be incomplete without calling attention to Article VIII of the Constitution of Michigan. Among other things, this section precludes the provision of public monies for non-public schools. Accordingly, any serious attempt to reform education in Michigan requires that proponents of choice consider amending, changing or abolishing this section which prohibits payments, credits, tax benefits, deductions, and vouchers for parents who exercise their choice to demand better schools for their children. This provision was drafted in large part by the protectors of the public school monopoly, teacher unions.
To be sure, changing the state constitution will not be easy. It will require committed individuals and groups. The children of Detroit and Michigan demand no less.