"Our chief electoral officer authorized an investigation be initiated to determine if contribution limits of $30,000 were exceeded by an individual donor contrary to the financial filings of a political party," Elections Alberta spokesman Drew Westwater said Tuesday night in an email.
"If we receive full co-operation of all the parties concerned we hope to complete our investigation expeditiously. "
The investigation flows from complaints sent to chief electoral officer Brian Fjeldheim last week by the opposition NDP and Wildrose parties.
Wildrose Leader Danielle Smith said the investigation needed to go forward.
"These allegations are serious if they're true, and they need to either be affirmed or need to be dispelled for the sake of all parties involved," said Smith.
"We think the allegation that there was a single $430,000 contribution (from Katz) needs to be investigated, and we're glad the chief electoral officer agrees.
"Hopefully we'll get to the bottom of it. If there is wrongdoing, we hope to see a prosecution."
The issue made headlines last week, when Elections Alberta documents revealed that Katz, his associates, and members of his family donated $300,000 to Premier Alison Redford's party in the spring election campaign.
The figure represents 20 per cent of all the money raised by the Tories, who took 61 seats to 17 for the Wildrose in the 87-seat legislature in the April 23 election.
There have been published reports that Katz paid for the donations plus more in one $430,000 cheque.
Under campaign fundraising laws, no one person or organization can donate more than $30,000.
Progressive Conservative party spokesman Kelley Charlebois could not immediately be reached for comment, but has said they have the documentation to prove the contributions are legitimate and legal.
A spokesman for the Katz Group declined comment.
Westwater has said that while it's permissible in some cases for one person to contribute a cheque for more than the $30,000 limit, it's up to the parties to conduct due diligence to make sure they have proof that no one person contributed more than the maximum.
Fjeldheim has the power to demand financial records and issue fines.
The Wildrose and the NDP have been hammering away at the Tories over the issue in recent days in question period.
They say the Tories are in a clear conflict of interest because Katz owns the chain of Rexall pharmacies that are impacted by government health policies.
Earlier Tuesday, NDP Leader Brian Mason asked Health Minister Fred Horne why, two months after the election, Redford's government changed the health schedule to almost double the amount of money pharmacists receive for delivering flu shots.
Pharmacists used to get about $11 from taxpayers for each flu shot, but now get $20 a shot.
A nurse who gives the same flu shot in a doctor's office gets about $10.
Horne said the change had been in the pipeline for a long time as part of a broader attempt to use pharmacists to lighten the workload of doctors.
"This government, in our last budget, reduced the prices that we pay in our public plans for generic drugs in order to fund that very service, which Albertans report as tremendously convenient and effective," said Horne.
But Mason said later that whether it's true or not, perception is also reality.
"They (the Tories) are going to be dogged by a cloud of doubt, to put it mildly, about their motives, whenever they deal with anything to do with pharmacists or to do with the Edmonton Oilers."
Katz has been seeking a casino licence and $100 million in direct funding from the province for a new arena for his NHL team.
Finance Minister Doug Horner said Tuesday he has met with Katz officials but said he has told them there will be no direct funding or casino licence changes.
Municipal Affairs Minister Doug Griffiths has said while there will be no direct funding, the City of Edmonton can use provincial infrastructure grant money to build the arena.
Funding is only one issue facing a new arena for the Oilers.
The deal with the city to build the $475-million facility stalled earlier this month over profit sharing.
City officials walked away from the table after Katz refused to meet with them in public at city council and explain why he wanted to alter the existing deal to deliver another $210 million in public money to him.
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