The state Supreme Judicial Court has ordered further argument in a challenge by local and municipal groups to stop the massive redevelopment project at the site of the defunct Boston Regional Medical Center site on the Middlesex Fells Parkway in Stoneham.
In a decision handed down today, the court sent back to the lower courts a single question of law, siding on that issue with the plaintiffs, which include the Friends of the Middlesex Fells Reservation and the City of Medford.
The justices did agree with the developer on three of four claims of the previous decision by the lower court that threw out the case.
The judgment is the latest round of legal sparring that has stretched since 2000, when the developer, now known as Fellsway Development LLC, first sought approval from state environmental officials for 310 housing units and a 225,000 square-foot office building at the 40-arce swath, which is surrounded by the state-controlled Middlesex Fells Reservation, the Globe reported in June.
Filed under the state's Chapter 40B affordable housing law, a quarter of the living space in the mixed-use project would be designated affordable.
At issue now for the lower court will be legal questions surrounding the developer's alleged attempt to improperly separate from the larger project road improvements to two rotaries on the historic Fellsway necessary to accommodate added traffic brought by the proposed complex, said Barry Fogel, attorney for the plaintiffs.
That agreement was formalized in a memorandum of understanding signed by the developer and the DCR that placed in escrow $1.8 million for the road construction, while the agency agreed that the project did not require DCR permits to go forward, potentially sidestepping state law that would require environmental study of the changes to the scenic thoroughfare, Fogel said.
The argument against splitting off the road work also hinges on an interpretation of a section of environmental law against dividing a development project into phases or parts to evade a full environmental review by the state.
In a brief phone interview, Kerry T. Ryan, attorney for the developer, said that he was pleased that the high court decided mostly in his client's favor, he said.
"It's a very limited issue that the court sent back," Ryan said. "We're pleased that the SJC agreed with nearly all our arguments."
The case will next be sent back to a superior court judge, who will determine if the memorandum meets legal muster and does not violate state environmental law.