Following the December approval of a 100-unit affordable housing development in Charlestown, a group of neighbors is suing Mayor Michelle Wu and the Boston Planning & Development Agency to block the project.

The group alleges the BPDA didn't take the neighborhood's opposition to the plans into account at an October meeting about the development, the Boston Globe first reported. In the lawsuit, filed Tuesday in Suffolk Superior Court, the group argues that the agency violated its First Amendment rights.

"Clearly, the BPDA Decision was rubber-stamped by the BPDA without any proper fact finding or a proper public process as required by Article 80 of the Zoning Code," the lawsuit says.

The development team is a partnership of the Planning Office for Urban Affairs, which is an affiliate of the Archdiocese of Boston, and St. Francis House. It had requested to waive the agency's Article 80 process, which is used to review projects of 50K SF or more. Though the project did go through public meetings and comments, City Councilor Gabriela Coletta said at a December BPDA meeting that an impact advisory group never met to discuss the project.

The group also raised concerns about the development's impact on the neighborhood, including increased traffic, lack of amenities and parking, and the threat of overburdening the local healthcare system.

The BPDA declined to comment on the lawsuit, and POUA didn't respond to Bisnow's request for comment.

The affordable housing project, which would redevelop the shuttered Constitution Inn in the Charlestown Navy Yard, was approved at the December BPDA board meeting. During its approval process, the developer cut the number of units in the project from 126 to 100 and agreed to bring on a security detail to help make residents feel safer.

Of the 100 affordable units, 52 would be restricted to households with incomes between $30K and $82K, while 48 would be supportive housing for women- and veteran-led households.

The opposition from neighbors against new affordable housing development isn't unique, with other projects in the city seeing similar pushback and even legal action.

In January, Dorchester-based Epiphany School sued the BPDA and developer Trinity Financial over the approval of a four-story, 72-unit affordable apartment building at 150 Centre St., the Globe reported. The school argued the project went through a "problematic approval process."

"By trying to jam this down the throats of the neighborhood ... it seems so contrary to how Mayor Wu talked of not building buildings, but building community," Epiphany's founder, the Rev. John H. Finley IV, told the Globe last month.