Philadelphia’s chief legal officer is leaving city government for private practice, returning to Am Law 100 firm Ballard Spahr and filling a longtime vacancy in the firm’s office managing partner position for its hometown of Philadelphia.

City Solicitor Marcel S. Pratt, who currently leads the 330-employee Philadelphia Law Department and serves as general counsel to the mayor and all city departments, plans to serve in his current position until Dec. 10 and join Ballard Spahr on Jan. 19. Throughout his two-year tenure with the city, he has spent much of his time advocating for historically marginalized populations and challenging the Trump administration in immigration-related litigation.