The state’s highest court has made clear that communities subject to the law must allow for additional, responsible development – and that the law is mandatory, not voluntary,” Attorney

The state’s highest court on Wednesday upheld the controversial MBTA Communities Act as a constitutional law that the attorney general has the power to enforce with legal action, but also ruled that existing guidelines are “unenforceable” because the Healey administration failed to roll them out properly.

The decision makes clear the state's authority over Milton and 176 other municipalities affected by the so-called MBTA Communities Act, an effort by the state to address the housing crisis. It was signed into law by former Republican Gov.