Take the following as truth: She spent 20 years as a litigator, first at Hufstedler, Kaus  and  Ettinger in Los Angeles, where she combined her love of science with her passion for litigation as an environmental law specialist, and then at Morrison  and  Foerster, where the firm's large environmental group and other science-based divisions gave her room to expand her practice area.
Then the following statement: "She was a lawyer at several firms before specializing in environmental law at other firms." is true, false, or inconclusive?