The John Adams Courthouse, seat of the Massachusetts Supreme Judicial Court is shown from Pemberton Square in downtown Boston in 2021. Photo by Sam Doran | State House News Service

First it lost a six-figure state climate change defense grant. Now, Milton is facing a lawsuit after voters rejected zoning that would have complied with the state MBTA Communities law.

Attorney General Andrea Campbell filed suit against the town Tuesday morning asking the state’s highest court to force Milton to comply with the law.

“The housing affordability crisis affects all of us: families who face impossible choices between food on the table or a roof over their heads, young people who want to live here but are driven away by the cost, and a growing workforce we cannot house,” Campbell said in a statement. “The MBTA Communities Law was enacted to address our region-wide need for housing, and compliance with it is mandatory.”

Campbell had issued an advisory to the 177 towns and cities covered by the law last year that compliance was not optional. The 12 communities with MBTA subway and bus rapid transit service had faced a Dec. 31, 2023 deadline to pass zoning mandated by the law. Another 130 communities with commuter rail stations, or which border those towns, face a Dec. 31, 2024 deadline to do the same.

The law requires towns and cities to allow for moderately-sized multifamily development by right in areas near transit stops, but lets them count existing buildings towards that goal.

Campbell’s lawsuit asks the state Supreme Judicial Court to confirm her guidance that compliance with the MBTA Communities law isn’t optional for municipalities, order the town to come up with zoning that complies and, if the town still doesn’t comply with the order, consider appointing a special master to work out new, compliant zoning and ban enforcement of any part of Milton’s “zoning by-law, rules, or regulations” that might be inconsistent with the MBTA Communities law and the state guidelines implementing it.

The lawsuit comes the same day Wrentham’s Select Board is scheduled to debate whether or not to send letters to Gov. Maura Healey and the town’s state legislators opposing the law.

In a referendum forced by opponents under the town’s bylaws, Milton voters on Feb. 14 rejected a zoning package passed by Town Meeting members in December, 5115-4346. Turnout in the election was just under 45 percent of the town’s 20,830 registered voters. That zoning package would have upzoned small areas around some of Milton’s stops on the Mattapan trolley line, which connects the MBTA Red Line’s Ashmont terminus to its Mattapan Square bus terminal just over the Milton town line in Boston, along with an office parcel and some state-owned parking lots along the Southeast Expressway.

In its first meeting after the referendum, Milton’s Planning Board had struggled to come up with a way forward.

“We need every community to come together and do their part to make housing more affordable. I’m grateful to Attorney General Campbell and her team for taking this important step today to enforce compliance with the MBTA Communities Law. This is not just about one community – but about the future of our workforce, our economy, and our entire state,” Gov. Maura Healey said in a statement issued by Campell’s office.

The attorney general’s lawsuit also marks a dramatic escalation in the battle over the MBTA Communities law. In a letter to Milton officials notifying them of the administration’s revocation of a $140,800 climate change-preparedness grant in light of the referendum vote, Housing Secretary Ed Augustus also sought talks with local leaders to figure out a new zoning plan that would be acceptable to both supporters and opponents.

The same press release from Campbell’s office announcing the lawsuit also sounded the same notes, quoting Augustus as saying his office “is hopeful that we can continue working with Milton to bring the town into compliance and build a stronger, more affordable Massachusetts for everyone.”

In a statement, Greater Boston Real Estate Board CEO Greg Vasil said his organization “applauded” Campbell for filing the suit, saying “the only hope for Massachusetts to solve its crushing housing crisis is for communities across the state to philosophically commit and operationally lay the groundwork for the production and construction of more housing.”

Lawyers for Civil Rights, a legal activist group that is currently suing the town of Holden for failing to file a compliance plan last year – the first stage in following the MBTA Communities law – also issued a statement lauding the attorney general.

“As LCR has been saying since 2022, any municipality that refuses to comply with MBTA Zoning Law is selfishly—and illegally—entrenching an unacceptable status quo. The law explicitly requires every covered community to help combat the affordable housing crisis by allowing for more multi-family housing development. It also aims to curtail racially segregated housing patterns by generating more affordable options in historically exclusionary areas. Today’s suit brings us one step closer to a world in which all Commonwealth residents, regardless of their race or income, can secure quality housing in their neighborhood of choice,” Executive Director Iván Espinoza-Madrigal said in an email.