D.A. John Robertson is the chief prosecuting official of the Bronx actively opposing the efforts of the Manhattan D.A. to take over the Vincent Jackson murder case, once they found the real killer, Taz Partell, and filed to exonerate the wrongfully convicted suspect, Tony Shaeffer.
In spite of Robertson's legal challenges and territorial jurisdiction squabbles throughout the investigations, the efforts of the Manhattan prosecution was successful. (L&O: "Bronx Cheer")