The finance committee of the Board of Aldermen will hold a public hearing tonight on whether the Board should stop granting new tax breaks for affordable housing developments in New Haven, as requested by Mayor John DeStefano Jr.

Citing budgetary concerns and a lack of consistent policy in a letter to the Board of Aldermen, DeStefano called for a moratorium on granting affordable housing tax abatement agreements until a “comprehensive policy” for dealing with such contracts is created. In the meantime, all previous tax abatement contracts will remain in effect. The hearing will allow New Haven residents to voice ideas and concerns to the committee regarding the proposed moratorium.

The Elm City currently has about 30 tax abatement deals on properties targeting low- to moderate-income and disabled tenants, and these tax breaks result in annual revenue losses to the city of approximately $4 million, DeStefano added. Approximately 2,400 units of affordable and supportive housing in New Haven are covered by these tax abatement agreements — 20 percent of the city’s total 12,300 affordable renting houses.

“Recently, the Board of Aldermen has received several requests to approve new tax abatement agreements,” DeStefano wrote in the letter. “Rather than take a piecemeal approach, I think it is time to take a collective look at the overall picture.”

DeStefano called for aldermen to create an affordable housing tax abatement working group tasked with developing a “series of legislative and programmatic recommendations” concerning how the city assesses and taxes affordable and supportive housing developments. In his letter, he proposed that the working group consist of aldermen, City Hall staff members, and business and community leaders in the finance and development industries, suggesting that the set of recommendations be developed within six months of the working group’s establishment.

“I’m open to hearing what the mayor has to say,” said Ward 2 Alderman and chair of the tax abatement committee Gregory Smith. “There are probably some good components to it, and I welcome the discussion.”

Kelly Murphy, the city’s economic development administrator, said there is a wide range of affordable housing developments in the city, including both large developers and nonprofit organizations, that the Board of Aldermen should consult in the discussions of a tax abatement working group.

Properties in New Haven that benefit from tax abatement agreements include the King George Apartments on George Street, the Bella Vista apartment complex in Fair Haven Heights and Tower One/Tower East near the School of Nursing. The Mutual Housing Association, which runs the King George Apartments, won an abatement earlier this year when the city waived $206,330 in annual taxes for its properties.

“[These tax abatement agreements] are a good thing for affordable housing,” said executive director of the Mutual Housing Association Seila Mosquera. “We also believe it is important to pay taxes, and the city definitely needs to have clear guidelines on these agreements.”

The new “comprehensive policy” that DeStefano hopes aldermen will replace a system that he said needs “consistency.” Robin Golden, a clinical lecturer in law and Ludwig Community Development fellow at the Yale Law School, said that her law clinic has had experience with the city on tax appeals for low-income housing, adding that there are problems with how initial taxes are determined.

“Right now, individual building owners can apply to the Board of Aldermen to get a tax abatement,” Golden said. “And as is true with other things that go through the board, much depends on the applicant’s ability to generate support.”

While Golden said that there will “no doubt be some problems” that arise during the moratorium period if Aldermen pass the proposal, executive director of the Housing Authority of New Haven Karen DuBois-Walton ’89 said she does not think the policy would limit access to low-income housing.

Property tax revenue for the 2010-’11 city budget totaled over $216 million.

CORRECTION: Nov. 30, 2011

An earlier version of this article incorrectly stated Robin Golden’s gender. She is a woman. The article also misstated the number of units of affordable and supportive housing supported by tax abatement agreements.