Jeffrey Amestoy (born July 24, 1946) is an American retired jurist from Vermont. He served as Vermont Attorney General from 1985 to 1997 and as Chief Justice of the Vermont Supreme Court from 1997 to 2004. Amestoy is noted for having authored the majority opinion in Baker v. Vermont, the 1999 Vermont Supreme Court decision that led to the legalization of civil unions for same-sex partners in Vermont in 2000.