Activists have planned a "Lobby Day" demonstration at the State House Wednesday in support of the bill.
The Lobby Day organizers justify the bill based on equal pay for equal work.
"Since benefits form such a large part of an employee's compensation, the denial of such based on sexual orientation is simple discrimination," Triantafillou said.
The ACLJ newsletter made a case against domestic partnership benefits by saying that, "Christians and all other taxpayers will be forced to subsidize the lifestyles of homosexuals," under such laws.
Triantafillou put the argument another way to highlight what she called the unfairness of the current situation.
"Why should gays subsidize health care benefits for straight couples?" Triantafillou asked.
The ACLJ sees broader implications in the ordinance.
Their newsletter states, "if cities sanction homosexual marriage, even by implementing 'domestic partnership' benefits, it will turn our society and its laws upside down."