As a state senator, he led the passage of New York's Married Women's Property Act in 1848.
After losing the judicial election, Fine ran for a seat in the New York State Senate and won.
Fine's most significant legislation in the State Senate was his introduction of the Married Women's Property Act.
Members of the nascent women's rights movement in New York lobbied for the bill, most notably Ernestine Rose and Paulina Wright Davis, but it was blocked by the legislature for the next twelve years.
In 1847, Fine published a pamphlet calling for women's right to keep their own property after marriage, and reintroduced the bill in the legislature.