OTTAWA - Conservative senators are making a bid to cut short debate on private members' business just as the Senate is about to revive debate on a controversial bill that would force unions to publicly disclose details of their spending.

The timing of the two moves has sparked suspicions that the Harper government wants to whisk bill C-377 through the Senate, avoiding the scrutiny that prompted senators, including 16 Conservatives, to gut the bill the first time it came before the upper house.

In June 2013, the Senate sent C-377, sponsored by Conservative MP Russ Hiebert, back to the House of Commons with amendments that effectively eviscerated the bill, which critics have called unconstitutional, undemocratic and an invasion of privacy.

However, Prime Minister Stephen Harper prorogued Parliament before the House of Commons could consider the amendments and, in accordance with rules for reinstating legislation following prorogation, the bill wound up back in the upper chamber in its original form.

Little attempt was made to move it forward over the past year but Conservative Sen. Jean-Guy Dagenais has signalled that he will restart debate this week.

At the same time, a Conservative-dominated committee has issued a report recommending that private members' business be subject to time allocation to limit debate - a departure from the long-standing practice of applying time limits only to government business.

The Conservatives need only use their majority in the Senate to accept the report and put an end to unlimited debate on private members' bills.

James Cowan, Liberal leader in the Senate, said rule changes are usually implemented "on a consensus basis" by the Senate rules committee, with "give and take" between Conservatives and Liberals. But this time, he said the recommendation for limiting debate on private members' business was sprung on the Liberals by a sub-committee that was supposed to be examining a proposal to televise Senate proceedings.

"What this has to do with it, I don't know," Cowan said in an interview.

A spokesman for Sen. Claude Carignan, government leader in the Senate, said the rule change is "not intended in any way to limit the debate," but is aimed at preventing a single senator from delaying debate indefinitely.

"We believe that all bills should move forward and be subject to debate and ultimately voted on, including bill C-377 and including the two bills sponsored by Senator Cowan," Sebastien Gariepy said in an email.

Renewed interest in the bill comes two months after Hugh Segal, who led the rebel Conservative charge against the bill last time, retired from the Senate.

From his new perch as master of Massey College in Toronto, Segal predicted that "use of unprecedented time allocation on private members' bills like 377 would justifiably produce a fire storm."

"(Bill) 377 was badly drafted legislation, flawed, unconstitutional and technically incompetent when it was amended last time. Unamended, it has not now become perfect simply because one senator retired to do other things," he added in an email to The Canadian Press.

Although C-377 is a private member's bill, it has been backed by the Prime Minister's Office. It would require unions to publicly disclose any spending of $5,000 or more and any salary of more than $100,000.

The amendments approved by the Senate raised the spending disclosure threshold to $150,000 and the salary threshold to $444,000. Sixteen Conservative senators supported the amendments and four others abstained.

Critics maintain the original bill would infringe on provinces' constitutional power over labour issues, violate charter guarantees of freedom of speech and association and amount to an invasion of privacy.

Hassan Yussuff, president of the Canadian Labour Congress, said private members' bills are more likely to be flawed than government bills because MPs don't have access to the same vetting process that ensures legislation doesn't run afoul of the Constitution and Charter of Rights. Consequently, he said it's "absolutely critical" that parliamentarians have time to scrutinize private members' bills.

Yussuff believes the push to cut short debate on private members' bills is aimed not just at whisking C-377 through the Senate but also C-525, which would make it harder for federally regulated workers to join a union and easier to decertify a union.

"The fact that (Segal) is now departed, clearly the government felt that they don't have the same rigour in their own circles to scrutinize them, so they'll take the chance that if they can amend the Senate rules in regard to time allocation, they can get these two pieces of legislation passed sooner rather than later," he said in an interview.

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