Deborah was an agent with the Office.
The Kill Artist Edit
Deborah was a newly-assigned member of the Ottawa Station in Canada working against Tariq al-Hourani. She reminded Gabriel Allon of Leah. She accompanied Gabriel to dinner and they watched al-Hourani and Jacqueline Delacroix.
The English Assassin Edit
Deborah was a member of the team Gabriel Allon set up to shield Anna Rolfe; Gabriel specifically requested her from Ottawa. She worked independently.