A friend emails that, contrary to my theory that Agent Harris
was playing Tony and Phil Leotardo against one another, his
character may have been based on a real life FBI agent who picked
sides in the mob wars.
He passes on a Pittsburgh Post-Gazettearticle from 1998 that begins:
It was May 22, 1992. FBI agent Christopher Favo was briefing his
boss, Special Agent R. Lindley DeVecchio, who headed the task force
trying to end Brooklyn's Colombo crime family war.
Two men loyal to the Colombo faction led by Victor J. Orena had
been gunned down on a Brooklyn Street the night before, Favo
announced.
DeVecchio's reaction was not what Favo expected. The man charged
with stopping the violence cheered for the shootings.
"He slapped his hand on the desk and he said, 'We're
going to win this thing,' " Favo would recall two years
later. "And he seemed excited about it.