Tuppence Macintyre is a Deputy District Attorney in Los Angeles, and a close friend of Greg Weisman's. As a personal favor to Greg, she (along with Monique Beatty) did copious research on the true Scottish history of Macbeth that was eventually adapted into "City of Stone". 
It should be noted that Margot Yale was not based on Tuppence Macintyre. However, in one of Greg's last issues of Captain Atom, the character of Tuppence MacRae, Plastique's lawyer, was based on her.  Greg's friend would get another nod in Young Justice, with the character Tuppence Terror.