MIDDLEBORO — A Boston-based legal group is demanding Middleboro comply with state MBTA community zoning requirements that town officials have said could add 1,500 housing units in town. 

The town has 10 business days to provide the state with its plan to comply with a new zoning law that requires communities with MBTA service to provide a multi-family zoning district, according to a letter submitted by a group called Lawyers for Civil Rights.

“Greater Boston is mired in an affordable housing crisis and remains highly racially segregated,’’ the letter, signed by three attorneys, Jacob M. Love, Owen M. Sellstrom and Ivan Espinoza-Madrigal, reads in part. “Towns that decline to increase their multi-family housing are perpetuating both of these problems.’’

In a meeting in December, the Select Board opted not to submit an action plan, arguing among other points that Middleboro lacks the infrastructure to accommodate such housing changes. 

To comply with this legislation, Middleboro would have to establish at least one zoning district that would total 50 acres and have the capacity for 1,471 units, Town Planner Leeann Bradley has said.

Select Board members at their Feb. 13 meeting also stated that the law does not require that additional housing must be affordable. 

Middleboro already has created and continues to create affordable housing, Town Manager James McGrail said. “We focus our efforts on affordable housing,’’ he said.

He said Bradley is reaching out to other communities that have not submitted plans to work together on the issue. According to the letter, the communities of Berkley, Carver, Holden, Marshfield, Raynham and Seekonk are not in compliance.

Town Select Board members at their Feb. 13 meeting also stated that the law does not require that additional housing must be affordable. “We need to look at more than just, Build more houses,’’ Select Board member Brian Giovanoni said. “There are other ways to solve this problem. Why don’t you let the towns figure out the best plan for it.’’

Questions were also raised about how much authority the Lawyers for Civil Rights has. The organization wrote it will “compel the town’s compliance’’ if Middleboro continues to “flout’’ the law.

“Exclusionary zoning practices have long been successfully challenged under the federal Fair Housing Act,’’ the letter stated. 

Select Board member Neil Rosenthal criticized the mandate as a “heavy-handed’’ and “one-size-fits-all’’ approach and took exception to the tone of the letter.

“The way the letter was phrased, you would think we were a bunch of racists here in Middleboro and of course that isn’t the case at all,’’ he said. “I take it as a personal insult to this community that they would push that agenda on us.’’