Budget officer Kevin Page published a legal opinion this week stating that 64 federal departments and agencies are breaking the law by withholding basic information from him.
In the legal opinion, lawyers said the Parliament of Canada Act requires the federal government to release financial and economic data to the parliamentary budget office in a timely matter.
Baird did not directly address the legal opinion in the House of Commons, but under questioning by the NDP he suggested Page is out of line.
"I have to say with great respect, I believe that from time to time and on occasion the parliamentary budget office has overstepped its mandate," Baird said.
Baird, standing in for the travelling prime minister, added that the Conservatives are committed to the same budgetary reporting mechanisms they once considered inadequate.
"Let me commit to this, that this government will continue to report to Parliament through the estimates, the supplementary estimates, quarterly reports and the public accounts, all the fiscal information this Parliament needs to do its job."
The PBO was created under the Conservatives' Federal Accountability Act in 2006 with a mandate to provide independent analysis of the state of the country's finances, government estimates and cost estimates of new programs.
"By establishing a parliamentary budget authority, the legislation would ensure parliamentary committees have access to independent and objective analysis on economic and fiscal issues," Baird, the lead minister on the Accountability Act, told a committee in May 2006.
Diane Ablonczy, the parliamentary secretary to the finance minister at the time, told the Commons in April 2006 the new PBO "would provide a financial reality check on the nation's finances."
"Again, because numbers that have been given to the House in different other settings have been, shall we say, not as reliable as they should be, we will put another reality check and another balance in place," said Ablonczy.
But since then the Conservative government has frequently sparred with Page — with Finance Minister Jim Flaherty going so far as to call him "unbelievable, unreliable, incredible."
While criticizing Page's various budgetary analyses, the Conservatives had never before suggested the PBO had no right to examine the books — until Tuesday.
Page's office wants to know how many employees and what programs are being eliminated under the government's 2012 cost-cutting plan, in order to check whether the advertised cost savings are credible.
But only 18 of 82 federal organizations complied with his request for more details. The powerful Clerk of the Privy Council then informed Page no more information would be released until all affected employees have been notified sometime this fall.
In the meantime, the Conservative majority voted the budget implementation bill through the House this week, with Senate approval pending.
NDP Leader Tom Mulcair called Baird's comment about mandate creep "a warning that Kevin Page has made the ultimate mistake: he doesn't tell the Conservatives what they want to hear and he actually wants to be able to say the truth to the Canadian public."
Bob Rae, the Liberal interim leader, said it was "a smear without substance or foundation" and accused the Conservatives of "cutting away at the authority and independence of the very people that they appointed in the first place."
Baird's office did not respond to a request for specific examples of the parliamentary budget office exceeding its mandate.
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