Liberal justice critic Sean Casey wrote MacKay on Friday, arguing that he has a legal duty to ensure that public affairs are conducted lawfully.
In particular, Casey said MacKay has a statutory obligation to ensure enforcement of Sec. 16 of the Parliament of Canada Act, which so far appears to have been ignored by the RCMP as it investigates allegations against Sen. Mike Duffy and Nigel Wright, Prime Minister Stephen Harper's former chief of staff.
The section says it's an indictable offence, punishable by up to a year in prison, for anyone to offer compensation to a senator for services rendered in relation to any claim, controversy, charge, accusation, arrest or other matter before the Senate. It's also an offence, punishable by a fine of up to $4,000, for a senator to accept such compensation.
Wright, has admitted giving $90,000 to Duffy so the senator could reimburse the Senate for disputed living expense claims.
The RCMP is alleging that the pair engaged in bribery, fraud and breach of trust, as defined in the Criminal Code. Neither Wright nor Duffy has been charged with any offence.
Some parliamentary law experts are puzzled why the Mounties have not so far mentioned Sec. 16 of the Parliament of Canada Act. Unlike the Criminal Code provisions, the act does not require proof of intent.
In his letter Friday, Casey reminded MacKay that the Department of Justice Act "places an explicit duty on you, as minister of justice and attorney general, to 'see that the administration of public affairs is in accordance with the law.'"
And he called on MacKay to ensure the Parliament of Canada Act is enforced in the case of Wright, Duffy and the more than a dozen other individuals who played a role in hammering out the deal with Duffy.
RCMP documents filed in court have shown that multiple senior PMO staffers, senators and Conservative party officials were involved in the deal, whereby Duffy publicly announced he'd repaid the Senate in return for a watered-down audit and Senate report on his conduct and assurance that there'd be no question about his eligibility to sit as a senator for P.E.I., although he lived primarily in Ottawa.
"I note that while the RCMP continues Criminal Code investigations into the actions of Mr. Wright and Mr. Duffy, there seems to be silence about the actions of these other individuals and whether they might be prosecuted under the Parliament of Canada Act," Casey wrote.
"It is critical that the public affairs of Canada be conducted in full compliance of the law."
In a later interview, Casey said MacKay should "invite" the RCMP to consider expanding its investigation to include the Parliament of Canada Act.
"I don't think that's out of line. The RCMP will then do what they will," Casey said.
"But I don't think it's good enough for the chief legal adviser to the government to sit back and do nothing in the face of everything that we know."
However, MacKay said Casey is essentially urging him to politically interfere in a police investigation.
"As Liberal justice critic, and a lawyer himself, Mr. Casey surely knows that the Public Prosecution Service of Canada (PPSC) is an arms-length, independent agency," MacKay said in a statement issued by his office.
"Our government made the PPSC independent to avoid the kind of political interference or bias in Crown prosecutor decisions which occurred under the previous Liberal government's watch. Given the independence of the PPSC, Mr. Casey's letter is better addressed to the Director of Public Prosecutions."
Although the PPSC would be responsible for prosecuting any charges that were laid under the Parliament of Canada Act, spokesman Dan Brien said the office does not initiate or direct police investigations or advise them on which laws to apply.
The RCMP have declined to comment on why the Parliament of Canada Act is not being considered.
Casey said his "best guess" is that the Mounties are reluctant to use Sec. 16 because there has never before been a prosecution under it — and, therefore, no case law as to how it would be interpreted by the courts.
But, like some parliamentary law experts, Casey said the act seems to apply more directly to the Wright-Duffy deal than the Criminal Code and appears to set "a lower threshold to establish a case."
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