PROVIDENCE — Mayor David N. Cicilline submitted to the City Council leadership on Tuesday an ordinance that would ban indoor prostitution in the city, imposing a $500 fine and a potential 30-day prison sentence on violators.

Responding to questions about the proposal’s constitutionality, Cicilline maintained that the city has the right to enforce such an ordinance.

State law, he said, is silent on the issue of prostitution behind closed doors (but clearly bans soliciting sex outdoors) and proposals to close this apparent legal loophole are still pending before the General Assembly, which recessed in July.

“There is no conflict with what is proposed in this ordinance and what has been enacted already in state law. The argument has been made that state law supersedes, that local ordinance cannot preempt state law,” Cicilline said Tuesday. “But if the General Assembly doesn’t enact anything [dealing explicitly with indoor prostitution], then we have not preempted anything.”

He added: “People will [also] make the argument that the General Assembly has already enacted legislation [with respect to prostitution generally], but we’ll be able to make a very good argument that we are dealing with a different subject than the current law.”

The proposed ordinance must be approved in two votes by the council and signed into law by the mayor. Cicilline has urged the council to move quickly on the matter.

Cicilline says the proposal is not an attempt to overshadow the General Assembly’s efforts on the issue.

“While the Rhode Island General Assembly continues to work to enact laws on the state level, we have the responsibility to put an end to indoor prostitution that has sprouted up in our neighborhoods disguised as so-called spas,” Cicilline said in a letter to the council. “I believe it is important to adopt a city ordinance now to ensure, in the interim, that we do everything in our power to stop this destructive activity in our city.”

Cicilline proposes an amendment that requires massage parlors and health clubs be licensed by the city Bureau of Licenses.

The proposed new language would seek to impose penalties on those who profit from prostitution, their customers, and the landlords that lease space to suspected brothels, the mayor said.

If found guilty, those accused would face, for each offense, a $500 fine and/or imprisonment of up to 30 days, which is the maximum penalty allowable for municipal-level violations (the proposed ordinance would be adjudicated by the Municipal Court).

City Council President Peter S. Mancini and Councilman Michael A. Solomon, who chairs the council’s ordinance subcommittee, will sponsor the ordinance. Solomon said the ordinance may be introduced as soon as the council’s Thursday meeting, where it will likely be referred to the council’s ordinance committee.

pmarcelo@projo.com