But just as in “Weiner,” the filmmakers have a gift for capturing colorful personalities in high-pressure political environments. Our characters here include the perpetually rumpled Lee Gelernt, who’s representing an immigrant woman separated for months from her young daughter; Brigitte Amiri, who’s defending a teenage immigrant woman who, after being raped, is barred from an abortion in Texas; Dale Ho, a fastidious lawyer arguing against a citizenship question on the U.S. census; and Josh Block and Chase Strangio, who oppose the Trump administration’s ban on transgender soldiers serving in the military.

Tracking these cases for nearly three years, “The Fight” burrows into life at the ACLU. In a guided tour of their New York offices, Ho acknowledges it’s a unique culture. “There are probably more tattoos and piercings here at the ACLU than there are at the DOJ,” he says.

Part of the film’s pleasure is in how the directors juxtapose the weighty, righteous causes of its attorneys with their humbler, eminently human lives. A win in the abortion case is celebrated by the commuting Amiri with a glass, she exclaims, of “Train wine!” In the midst of a dramatic turn in the family separation case, Gelernt is helplessly unable to charge his phone. When a younger colleague hands him a charger and directs him to his computer’s USB port, she might as well be giving him instructions on how to reach Neptune.

Still, the stakes are always present. While “The Fight” concentrates on the ACLU’s legal crusaders, the few glimpses it affords to those the attorneys are representing are powerful. Perhaps it could use more of people outside the courtroom. But the few scenes, for example, of immigrant parents talking about their children being taken away from them are devastating.