LEWISTON — James Tierney, former attorney general of Maine and former majority leader of the House of Representatives, will present “Immigration in Maine: Past and Future” at 7:30 p.m. Monday, Oct. 20, at the Bates College’s Edmund S. Muskie Archives, 70 Campus Ave.

With the aging of Maine’s population posing a threat to economic vitality, “we need more people,” Tierney told a University of Maine audience in a landmark 2002 talk about diversity and immigration that has become a standard reference for state and community leaders.

“We must see immigrants as an opportunity,” Tierney said. “California, Texas, New York, Florida, Arizona, Washington, the states that are our country’s engines of economic growth, are culturally diverse.”

Tierney now serves as the director of the National State Attorneys General Program at Columbia Law School, where he has taught law since 2000. He also lectures at Harvard Law School and works as a consultant to attorneys general around the country, offering guidance on the effective performance of their office.

Tierney served as special counsel to the attorney general of Florida during the contested and still-controversial 2000 U.S. presidential election.