Only Duffy and Gerry Donohue know for sure, and they aren't talking.
Donohue, a retired TV technician, is the latest person to get caught up in the scandal swirling around the senator.
The Mounties allege Duffy paid Donohue $64,916 out of his office budget over four years for little or no work.
None of the allegations against Duffy or Donohue have been proven in court. But the latest batch of RCMP court filings shed some light on their purported dealings.
Their friendship dates back to the late 1980s. By then, Donohue was already a veteran of the TV news business. He was working at an Ottawa television station that had just scored a major coup by luring Duffy away from his high-profile CBC gig to host a Sunday political talk show.
Over long hours working on the fledgling "Sunday Edition" program, the pair became friends.
Donohue was a union representative at the station before he became head of human resources. People who worked with him say his sudden move from the union to management rubbed some people the wrong way.
Health issues led to Donohue's retirement in 1997. He and his wife bought a house on the outskirts of Ottawa in 2002.
After Donohue retired, he incorporated a company called Maple Ridge Media. Corporate documents list Donohue's wife and son as directors of the company.
Donohue told RCMP investigators the company sat dormant for years.
In 2003, Maple Ridge Media became a local distributor for insulated concrete forms. He changed his company's name a few years later to Ottawa ICF to better reflect the nature of its work.
Duffy asked Donohue to come work for him as a consultant after he got his Senate appointment. Donohue told the RCMP that he agreed, even though he had never before done any consulting work.
"Duffy would call him with a subject such as obesity, or being a Conservative, and he would do Internet research on the topic and provide advice or an opinion," the Mounties say in their court filing.
"Over the period of his contracts with Duffy, he did not produce any tangible document, report or work product."
Donohue told the RCMP he would sometimes watch the news and chat about it with Duffy.
Donohue also told the Mounties he never personally received any of the money because he has been on disability. He explained that he earned money for his company, which consisted of his wife and son.
Both of them declined interviews with the Mounties and have sought out a lawyer.
Donohue stopped working for Duffy sometime last year. He told the Mounties he sold his business last March, but an Ontario government document indicates Maple Ridge Media was dissolved in October 2011.
Donohue didn't return a phone call, and his wife has yet to reply to an email.
When reporters showed up at their home this week to try to get answers to that $65,000 question, Donohue called the police.
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