UPS has denied health benefits to some same-sex couples in New Jersey. Gay rights advocates say the shipping company's move illustrates the limitations of the state's civil union law.

UPS provides health benefits to its employees' spouses, including married gay couples in Massachusetts. But, it says the Garden State's decision to recognize same-sex relationships as civil unions, rather than marriages, has tied its hands. In a letter to one UPS driver and her civil union partner, the company concluded that "New Jersey law does not treat civil unions the same as marriages."

The letter says if the state had done that, the driver's civil union partner could have been included in the health coverage plan as a spouse.