She Sought Change at the Manhattan D.A.’s Office. Now She Wants to Lead It.

Lucy Lang has spent most of her career as a criminal-justice reformer. But is she too close to the system to bring about real change?

Lucy Lang is a squeaky wheel, a meddler, a self-described noodge. A granddaughter of the philanthropist Eugene Lang, she is bent on the constant improvement of her surroundings. In the dozen years she spent working at the Manhattan district attorney’s office, she developed a reputation for pushing reforms that created new opportunities for those charged by prosecutors — but she was also stymied by a leadership team that did not always want things to change as fast as she did. Now Ms. Lang, 40, wants to be in charge of that change, running against seven other Democrats to replace her old boss, Cyrus R. Vance Jr., as the Manhattan district attorney. In April, she gave her own campaign half a million dollars, according to campaign finance reports, in hopes of staying competitive with two leading candidates, Tali Farhadian Weinstein and Alvin Bragg. While little quality polling has come out in the race, the few available surveys have shown her trailing only Ms. Weinstein in popularity.