An organization whose stated goals include “restoring traditional moral principles’’ to government policies is challenging the move by the administration of Gov. Janet Napolitano to extend health care and other benefits to the domestic partners of state and university employees.

In objections filed Monday with the state, the Center for Arizona Policy contends the proposal violates both the state constitution and various statutes.

Peter Gentala, the organization’s legal counsel, said the question of who does — and does not — get benefits is solely reserved for the Legislature.

Gentala also said providing benefits runs afoul of what he said is the “state policy favoring marriage.’’

And Gentala hinted if the state adopts the policy, his organization may challenge it in court.

The move by Bill Bell, the governor’s director of the Department of Administration, comes a year after voters narrowly rejected a proposed constitutional amendment to prohibit government agencies from providing the same status as married couples to those who are not married. It would specifically have outlawed what is being proposed.

The proposed rule change would affect about 65,000 state and university workers, at an initial cost of up to $5.6 million a year for active employees and another potential $306,000 for retirees who also would be eligible.

Plans are to have it in place by Oct. 1.

Gubernatorial press aide Jeanine L’Ecuyer said the plan did not originate with Napolitano but instead with Bell. But L’Ecuyer said the governor supports the move.

“One of the things the Department of Administration has pointed out is that it helps to keep Arizona competitive in the job market,’’ L’Ecuyer said.

Several communities, including Tucson, Scottsdale, Tempe, Phoenix and Pima County, already extend some benefits to domestic partners of state workers, as do a number of major private employers.

Current state rules generally limit benefits to a spouse or dependent child of an employee. The new rules add domestic partners and their children to that list.

It specifically defines that category to be someone living with the employee for at least a year and expected to continue living with that person. There is no reference to the gender of the partner.

It also requires a showing of financial interdependence as shown by factors like a joint bank account, both being parties to a lease or naming the other person as a beneficiary on a will. And there also needs to be an affidavit by the employee that there is a domestic partnership.

Gentala said the Legislature only gave the Department of Administration the power to use tax dollars to provide benefits to dependents and spouses of state workers.

“They weren’t saying you can go out there and create a new legal status called domestic partner, which looks like marriage,’’ he said. Gentala said that was done on purpose because the Legislature, which sets state policy, has determined that being legally wed is preferable to living together.

“The existing employment policy promotes marriage and is an incentive for employees to be married, have families,’’ he explained. “It’s recognizing those decisions and rewarding them with appropriate state benefits.’’