Activists and scholars are marking the 40th anniversary of the first ruling issued in an affordable housing lawsuit that has been debated in New Jersey ever since.

The Southern Burlington County branch of the NAACP sued Mount Laurel Township, arguing that the Philadelphia suburb's zoning laws discriminated against the poor. On May 1, 1972, a state judge agreed.

What each town's responsibility is to house the poor has been debated in courts and politics ever since.

A pair of landmark state Supreme Court rulings, which said towns had to include the possibility of lower-income people living there, have been cited as both an important expansion of citizen's rights and an overreaching court intrusion into local decisions.

At a conference Thursday at Princeton University, scholars discussed the impact of the rulings.

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