Volpe's role

Things are now becoming clearer. Why was Volpe mentioned? Apparently Grewal wanted a public apology from Volpe: he admits as much here.

From the story linked to above:

On the tape, Mr. Murphy is overheard referring to discussions he's had with Volpe.

“Mr. Grewal had suggested that perhaps some action could be taken with respect to the investigations launched by the RCMP and ethics commissioner,” said Mr. Reid.

“Mr. Murphy appropriately insisted that those were independent processes and that nothing could or would be done.

“Mr. Grewal asked if Mr. Volpe might at least say a gracious word about him in public and Mr. Murphy undertook to raise the matter.”

Mr. Grewal agreed he wanted Mr. Volpe to retract his allegations. But he angrily denied ever asking anyone to interfere with an investigation.

“It's absolutely false,” Mr. Grewal said in an interview. “I told these guys, ‘This minister owes me an apology.' Because the comments he made, he knew they were false.