"The end of the institution, maintenance, and administration of government, is to secure the existence of the body politic" — so begins the preamble to the Constitution of the Commonwealth of Massachusetts.

"It’s actually a bit of poetry in places," said renowned civil liberties lawyer Harvey Silverglate. "It’s a marvelous document. It is the leading charter for liberty in the Western Hemisphere and the oldest."

Silverglate is an unabashed admirer of the Massachusetts state constitution. Written mainly by John Adams, it was adopted by a majority vote of delegates from each Massachusetts town on June 15, 1780.

"Massachusetts' constitution is older than the U.S. Constitution, the Declaration of Rights older than the Bill of Rights," Silverglate said. "Both of them were something of a model for the federal constitution."

As you’d expect, there are quite a few similarities, between the Massachusetts Constitution and the U.S. Constitution, including three branches and a bicameral legislature. But there are also some significant differences, says Silverglate. Exhibit one: the Declaration of the Rights.

"Most people don’t realize that the Massachusetts Constitution has a Declaration of Rights that is broader, and more efficacious, and less limited than the Bill of Rights of the U.S. constitution," Silverglate said. "And that these provisions can be called upon to provide rights beyond anything that a federal court can or will enforce."

Consider the story of Elizabeth Freeman, an illiterate slave from Western Massachusetts. At a 1780 public reading of the new state constitution, a phrase from the Declaration of Rights caught her ear: "All men are born free and equal, and have certain natural, essential, and unalienable rights; among which may be reckoned the right of enjoying and defending their lives and liberties."

Freeman reasoned that by law, she should be free. The Court of Common Pleas agreed. The following year the Supreme Judicial Court cited her case as precedent in another slave case, effectively ending slavery in the Bay State. The SJC’s role as laid out in the constitution is exhibit two, says Silverglate, the other critical difference between the U.S. and Massachusetts constitutions.

"The Supreme Judicial Court sees its role more broadly than the U.S. Supreme Court sees its role in the federal system," Silverglate said. "The U.S. Supreme Court is always talking about the limitations on its authority, where as the Supreme Judicial Court has supervisory powers."

Silverglate says that as a court of general superintendence, the SJC has the mandate to protect, and a long tradition of protecting, the broad rights laid out in the state constitution.

"So this is a court that has a great deal of flexibility and exercises that flexibility," Silverglate said. "You hear the words a lot from the Supreme Judicial Court: 'We make this decision in the interest of justice.' You never hear that from the Supreme Court."

And not just in the distant past. In 2003, when Goodrich v. The Board of Public Health came before the SJC, the court decided that same-sex couples had the right to marry here in the Bay State — because it was in the interest of justice as defined by the state constitution.

"Justice [Margaret] Marshall and her cohorts who decided Goodrich were smart enough to base the opinion on the Massachusetts state Declaration of Rights," Silverglate said.

The section the decision was based on? Article I of the Declaration of Rights. The same passage that earned Freeman her freedom two centuries earlier.

The Massachusetts State Constitution — the first to be adopted by Constitutional Convention, and the oldest still-operating document of its kind in the world, was voted on and passed in Cambridge 235 years ago this week.

If you have a tale of forgotten Massachusetts history to share, or there's something you're just plain curious about, email us at curiositydesk@wgbh.org. We might just look into it for you.