Nigel Wright, former chief of staff to Stephen Harper, testified Wednesday as the star witness in the trial of Senator Mike Duffy. Mr. Wright quit the Prime Minister's Office in May, 2013, after it was revealed that he wrote a cheque to Mr. Duffy for $90,000 to reimburse taxpayers for questionable expense claims. The e-mails, tabled as evidence in the trial, show how the top staffers in the Prime Minister's Office dealt with the unfolding Senate expenses scandal in real time.