Born in Chicago, Illinois, on July 23, 1935, he grew up in Arlington, Massachusetts.
He graduated from Amherst College and received his Juris Doctor degree from Harvard Law School.
Hoyt also received his master's degree from Boston University.
In 1968, he moved to Vermont serving as deputy commissioner of taxation.
He served in the Vermont House of Representatives from 1974 to 1985 as a Democrat.