HARTFORD, Connecticut (CNN) -- The Connecticut Supreme Court ruled Friday that gay and lesbian couples have the right to get married.

The ruling makes Connecticut the third state, after Massachusetts and California, to decide its constitution mandates treating citizens equally when applying for marriage licenses, regardless of their sexual orientation.

"Interpreting our state constitutional provisions in accordance with firmly established equal protection principles leads inevitably to the conclusion that gay persons are entitled to marry the otherwise qualified same sex partner of their choice," the ruling said.

"To decide otherwise would require us to apply one set of constitutional principles to gay persons and another to all others. The guarantee of equal protection under the law, and our obligation to uphold that command, forbids us from doing so. In accordance with these state constitutional requirements, same sex couples cannot be denied the freedom to marry."

The decision would only allow gay couples the state benefits of marriage. The Defense of Marriage Act, passed in 1996, denies gay couples federal recognition of state marriages, which provides for federal benefits with regard to Social Security, taxation, immigration and others.

Connecticut, Vermont, New Hampshire and New Jersey have civil unions. View a map of where states stand on same-sex unions »

In 2005, Connecticut began to allow civil unions, intended to be marriage in all but name, without being forced by its courts. Two years later, Connecticut's Legislature tabled a bill allowing marriage.

Eight same-sex couple sued the state, saying that civil unions were not equal to marriage and that Connecticut's Constitution guaranteed them equal treatment.

In the dissent, one justice said he disagreed with the majority's opinion that "sexual orientation is a quasi-suspect class under our state constitutional provisions guaranteeing equal protection of the laws" because that point of view "unduly minimizes the unique and extraordinary political power of gay persons in this state."

A representative of Connecticut's commissioner of public health said he does not know when the state might start issuing marriage licenses to same-sex couples.

The suit was called Kerrigan and Mock v. the Connecticut Department of Public Health.

All About Same-Sex Marriage • Gay and Lesbian Relationships • Connecticut