David Lesser

Age: 59
Home state: Maryland
Cause: Consumer protection

A onetime bank general counsel who was winding down his own small manufacturing firm, Lesser answered a 2010 call for volunteers from the Office of Consumer Protection in Montgomery County, Md. Drawing on his legal expertise, he spends 15 hours a week investigating and resolving complaints; he's recovered tens of thousands of dollars so far. A big victory: identifying hundreds of plumbers who charged customers an average of $85 for sham permits when installing appliances — then getting retailers that had hired the scammers to guard against future fraud.

Says Lesser:

People often feel helpless when seeking redress. It takes a certain kind of perseverance and skill to succeed."