Before he left office in 2003 Dean made an agreement with the Secretary of State's office that some of his records would remain sealed for a decade.
On Thursday that time limit expired and about 80 boxes became public at the state archives in Middlesex.
Among the items in the records are boxes of correspondence Dean's office received about the Vermont Supreme Court's decision that led to the creation of same-sex civil unions.
In one exchange with then Roman Catholic Bishop Kenneth Angell, Dean asked Angell to work to prevent opposition to civil unions from leading to personal attacks against gays and lesbians.
Angell answered that civility is a basic tenet of Catholicism.