The public broadcaster received an A for its handling of Access to Information requests in 2011-12, up from an F for its performance two years ago.
Information Commissioner Suzanne Legault will release the latest report cards for the CBC and Canada Post on Thursday.
A copy of CBC's assessment, obtained by The Canadian Press, says the broadcaster has made "dramatic improvements" since getting the failing grade for its 2009-10 efforts.
Legault applauds CBC president Hubert Lacroix for showing leadership by making compliance with the Access to Information Act a priority.
The move "emphasized the importance of transparency throughout the institution" — an expectation backed up by training for employees at all levels on dealing with access requests, says the report card.
The access law allows people who pay $5 to seek federal files ranging from expense reports and email messages to briefing notes and internal audits.
Federal departments and agencies are supposed to respond to requests within 30 days, but often take much longer — sometimes missing their own extended deadlines.
As an ombudsman for users of the law, Legault has periodically looked at whether key institutions are meeting their legal obligations of transparency.
She discovered that in 2009-10, the CBC failed to answer almost 60 per cent of the requests it received within the required timelines. It took an average of 158 days for the broadcaster to respond.
In 2011-12, the percentage of timeline failures dropped to just over four per cent, and the CBC needed an average of 36 days to answer a request, says the latest report card.
"Challenges encountered in achieving compliance were resolved by putting in place a mechanism that allowed management to react rapidly when requests were not advancing according to standard deadlines," says the report.
The CBC proactively posts frequently requested information on its website, it adds.
Last year, the number of complaints Legault received about requests to the CBC "was still high," but reflected a 47-per-cent drop from two years earlier.
The CBC, Canada Post and other Crown agencies were brought under the access law by the federal Conservatives.
Special exceptions the government built into the law allow CBC to shield information related to journalistic, creative and programming activities.
The courts ruled last year that Legault has the right to examine this sort of information when she receives a complaint about it being withheld from release.
As a result, says the report card, Legault reactivated a number of complaints she had put on hold in 2008-09.
Her team "initially had some difficulty" obtaining responses to its investigative inquiries, but subsequent communication with CBC management improved things, says the report.
Legault's office began clearing a large backlog of requester grievances about CBC, but still had 234 as of Oct. 1., and stresses that, "to protect requesters' rights, the CBC must dedicate more resources to complaint resolution until this backlog of complaints is eliminated."
Canada Post was stamped with "red-alert" status for its poor performance two years ago.
Almost three-quarters of the applications the post office received in 2009-10 were not answered within specified deadlines — "one of the worst rates" the information czar had seen since starting to publish report cards over a decade ago.
It took an average of 190 days for the Canada Post to respond to a request.
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