Thomas M. Cooley's 'Treatise on Constitutional Limitations' celebrates its 150th anniversary


By Kristy Demas
U-M Law

In 1868, Thomas M. Cooley, former Michigan Law faculty member and dean, published “A Treatise on the Constitutional Limitations Which Rest Upon the Legislative Power of the States of the American Union.” This year marks the 150th anniversary of Cooley’s book, which Edward S. Corwin, a constitutional law authority and former president of the American Political Science Association, called “the most influential work ever published on American constitutional law.”

When it was first published, the treatise quickly became the authoritative guide on how state constitutions are formed and laws enacted. While Cooley referred to it as an “attorney’s companion,” the treatise’s impact was immeasurable, especially for its time.

The treatise was printed just as the Fourteenth Amendment was being ratified, according to the Michigan Law Library, and was considered to be significant.

“For Cooley, due process meant that the powers of government must be exercised in accord with the ‘settled maxims’ of the common law, especially its safeguards for the protection of individual rights,” the Law Library noted.

Cooley saw common-law constitutionalism as protective of individual liberty and that established principles, rather than procedure, should determine if an act—legislative or administrative—was due process.

Before coming to Michigan Law in 1859, Cooley ran his own legal practice while writing prolifically on politics and the law. In the 1850s his writings gained national attention, and he began working as a compiler of Michigan statutes. “The Compiled Laws of the State of Michigan: Published by Authority,” took him one year to complete and was approved by the Legislature in 1857—at which time he was appointed official reporter for the Michigan Supreme Court.

Cooley remained on the Michigan Law faculty until 1884—serving as dean from 1871 to 1883. In 1864, he was appointed the 25th justice of the Michigan Supreme Court, where he served with Justices Campbell, Christiancy, and Graves. Collectively they were called The Big Four for their influence on the state’s legal system.

Cooley retired from the Michigan Supreme Court in 1885. Once considered a potential U.S. Supreme Court appointee, he was never named. Instead, in 1887, President Grover Cleveland named him the first commissioner of the newly created Interstate Commerce Commission—where Cooley wielded considerable influence during his four-year tenure.

The State Bar of Michigan calls Cooley a “Michigan Legal Milestone,” referring to the influence of his treatise as well as his book, “The General Principles of Constitutional Law in the United States of America.” Both are included in the Liberty Library of Constitutional Classics.

His contributions to the University of Michigan and to his field are noted by the U-M Regents:

“His writing, especially his treatises on constitutional law, made his name and that of the University known wherever English law is read.”