Two years ago, Jaroslawa Zelinsky Johnson left her home on Institutskaya Street in Kiev as anti-government protests turned into violent battles with police and pro-regime forces.

The Euromaidan movement that rocked Ukraine in 2014 put the country in the hands of reformists that Johnson, a Ukrainian American and former managing partner of Chadbourne & Parke’s Kiev office, wholeheartedly supports. But now she has another fight on her hands, one that pits Johnson against her former firm.