He wrote poems criticizing slavery and celebrating the European revolutions of 1848, edited pro-Democratic newspapers, and founded the Michigan branch of the Free Soil Party in 1848.

[2] However, he was rewarded politically when in 1887 when President Cleveland nominated him to the Interstate Commerce Commission, one of the first independent agencies of the federal government.

The book discusses the particulars of taxes assessed against property and businesses, as well as legal remedies against illegal and unjust taxation.

[10] In 1878, Cooley completed and published his work A Treatise on the Law of Torts or the Wrongs Which Arise Independently of Contract.

One edition of Cooley's treatise on the subject matter of tort law was published in Chicago by Callaghan and Company in 1907.

As a collegial work, Cooley's treatise on torts made extensive use of citations to case law.

While Dean of the University of Michigan, Cooley had published his treatise The General Principles of Constitutional Law in the United States of America in March 1880.

[12] Corwin wrote, as to the Establishment Clause of the First Amendment of the United States Constitution (a clause contained within Amendment I), "[i]t [that Justice Story believed the United States Congress was still free to prefer the Christian religion over other religions, in contrast to modern Constitutional law and interpretation] is also supported by Cooley in his Principles of Constitutional Law, where it is said that the clause forbids 'the setting up of recognition of a state church of special favors and advantages which are denied to others.

'"[13] "This assumption," Robert G. McCloskey wrote as to the legal essentiality of the concept due process of law in The American Supreme Court, "was a product[,] no doubt[,] of many converging factors: the multiplication of 'welfare state' threats, the Macedonian cries of the business community and its legal and academic defenders, a growing awareness that an interpretation of due process[,] which seemed impossibly novel[—]and probably unnecessary a decade before[—]could be made acceptable by slow accretion[,] and might prove very useful in the cause of righteousness.

Cooley′s classic treatise[,] Constitutional Limitations, first published in 1868, had become a canonical text for jurists, and [Cooley's] support of due process in its emerging form gave the stamp of scholarly approval to an interpretation that seemed ethically more and more imperative.

Within his treatise The General Principles of Constitutional Law in the United States of America, on the subject of municipal corporations, Cooley wrote: It is axiomatic that the management of purely local affairs belongs to the people concerned, not only because of being their own affairs, but because they will best understand, and be most competent to manage them.

[16]In a contrasting legal theorem to that of Dillon's Rule (which posits that towns and cities have no independent authority except as explicitly or implicitly granted by a state legislature) the Cooley Doctrine proposed a legal theory of an inherent but constitutionally-permitted right to local self-determination.