Illinois state constitution vis-a-vis federal constitution

In state constitutions, more rights are expressly enumerated than in the federal Bill of Rights. In Illinois, its constitution contains all of the protections afforded in the federal Bill of Rights and much of the same language as well. It also contains further rights such as Crime Victim’s rights, right to remedy and justice, freedom from imprisonment for debt and more. Also, in the Illinois constitution the guarantee that the state shall provide free public education is expressed in article X, section 1. These additional rights explicitly outlined by the Illinois Constitution are clearly protected by law.

Unfortunately, that is where the simple comparisons end. Quite often, state constitutions serve to further define the constitutional rights that have already been named in the federal Bill of Rights, by either expanding their scope or limiting it. Two court cases in Illinois are examples of how Illinois constitutional provisions have been analyzed as either apart from or complementary to amendments in the federal Bill of Rights.

[...] In contrast to Quilici, where the interpretation of the Illinois Constitution served to further refine the definition of the Second amendment right to bear arms, the interpretation of the state constitutional provision in Pruneyard was construed to expand the definition of the First Amendment right to freedom of speech. Seven years after the latest Illinois Constitutional Convention, Supreme Court Justice William J. Brennan Jr. applauds decisions made in the manner similar to Quilici and Pruneyard. In an article in the Harvard Law Review, Justice Brennan expresses his philosophy that state constitutions are the ultimate protectors of civil liberties. [...]

[...] Justice Brennan, however, cites encouraging state cases that demonstrated that federal decisions are not entirely persuasive authorities in California, New Jersey, South Dakota, Hawaii and other states. Id, at 499. His philosophy encourages state courts to take into consideration their own constitutions, separate from the U.S. Constitution, in order to maintain the important dualistic balance of federalism in the United States: both the federal and the state government are to remain equal sovereigns. Shirley S. Abrahamson and Charles G. Curtis, Jr., US Supreme Court information about State Constitutions and Individual Rights (Oxford U. [...]