Chief Electoral Officer Brian Fjeldheim named the investigators in a letter to Opposition Leader Danielle Smith of the Wildrose party last month.
Retired Court of Queen’s Bench Justice Ernest Marshall has been appointed director of the investigation, while Don Vander Graaf and Dave Davies have been retained as independent investigators.
The investigators were selected due to "their particular expertise with these types of investigations," Fjeldheim said in his letter.
Elections Alberta spokesman Drew Westwater said the investigators are former police officers who have worked on financial cases in the past.
He said that they will "contact all the parties involved, question them about the details of the allegations, get their side of the story, get documentation to verify it — whether it's their own internal records or bank documents or records — to confirm or deny the allegations."
The investigators will then make a recommendation to the chief electoral officer. Westwater said that it's hard to say how long the probe will take.
Katz alleged to have made single donation
Elections Alberta only has three full-time finance employees so Westwater said it's standard procedure for larger, more time-consuming cases to be contracted to outside investigators.
"Based on the size and scope of this particular allegation, we've determined that an external team is required," he said. "We've used them before."
The Wildrose and New Democrats asked the chief electoral officer last year to look into the donations which could total more than $400,000.
Individuals are only allowed to donate $30,000 to a political party in an election year.
Documents from Elections Alberta released last fall show that Katz, members of his family, his executives and his company donated at least $300,000 to the Tories during last spring's election. Each individual received a receipt for $25,000 or $30,000.
However, a report in the Globe and Mail alleges that the donation was $430,000, given to the party in a single cheque.
News of the outside investigators comes one day after Alberta's ethics commissioner announced he would probe whether Premier Alison Redford was in conflict of interest when she chose her ex-husband's law firm to help litigate the province's tobacco lawsuit.
Mount Royal University political scientist Duane Bratt believes the Alberta PCs are in trouble, especially since the government is expected to soon table another deficit budget.
"The fall session was very difficult for the premier, for the government, but that was just in question period, that was just from the Opposition, that was just from the media," he said.
"Now you've got official investigations going on and we haven't even gone into the winter session yet, we haven't even released the budget."
Katz has not commented on the Elections Alberta investigation.