A Toronto city councillor's campaign manager offered to reimburse donors in cash if they donated the maximum amount allowed to his candidate, a secret audio recording now in possession of provincial anti-corruption police reveals.

CBC News has independently obtained a copy of the recording, made in the wake of the 2014 municipal election.

Julien Di Ciano, Coun. Justin Di Ciano's campaign manager and twin brother, can be heard soliciting donations, apparently from a childhood friend and the friend's girlfriend.

"OK, listen. I need you and Magda to give Justin a cheque for his campaign, for his political campaign, and I'm gonna cut it back to you in cash, OK?" Julien Di Ciano is heard saying to the friend, Brandon Sobel.

"We're going to do a fundraiser.… If you give $750 to the campaign, the city cuts you a cheque for 450 and I'm going to give you 300 in cash, so you're not out any cash."

Toronto had a contribution rebate program for the 2014 election, whereby someone who gave the maximum $750 to a council candidate would get $450 back from the city. The donor would only be out of pocket for the remaining $300.

The recording continues with Julien Di Ciano saying, "OK? You did it last time. You and your girlfriend both did it the last election. OK?"

Julien Di Ciano tells a childhood friend that he would get $300 cash for donation to brother's campaign 1:25

The audio only captures one side of the conversation and does not pick up Sobel's responses. But City of Toronto records show that Sobel and girlfriend Magda Chelminska each donated $750 to Justin Di Ciano's winning campaign, as well as his unsuccessful bid for the same city council seat in 2010.

Sobel confirmed in an email to CBC News that he and Chelminska both donated to the Di Ciano campaign. But, he said: "I do not remember ever being offered anything to donate, nor would I ever accept anything to donate to a friend's campaign."

In a phone interview, Chelminska said she thought she hadn't donated but wasn't entirely sure. She said she didn't know anything about a possible offer of cash in exchange for donations.

For his part, campaign manager Julien Di Ciano said in an email that he has "no recollection of any conversation I had with Brandon that includes your allegations.

"Irrespective of that, I never provided Mr. Sobel with any benefit to donate to my brother's campaign. I have reviewed all my financial records including June and July of 2015 when Brandon made his donation and there is not a single transaction to suggest any financial irregularity."

OPP has audio recording

The secret recording was made from inside the offices of Dunpar Homes Ltd. — a luxury home builder based in Etobicoke. At the time, Julien Di Ciano was a site supervisor for Dunpar. His office at Dunpar functioned as an unofficial campaign war room for his twin brother's municipal election campaign, multiple people have told CBC News.

Dunpar owner John Zanini said in an interview that he has no knowledge of whether his employee was making campaign calls from his company's offices.

Asked specifically whether Dunpar's offices, equipment or staff were used in any way to help the Di Ciano campaign, Zanini said: "Not to my knowledge."

CBC News has learned that a copy of the audio recording is now in the hands of investigators with the Ontario Provincial Police anti-corruption unit. The unit was called in to review allegations that Di Ciano and at least one other Toronto councillor might have benefited financially or politically from their relationship with developers. Officers have interviewed a number of people so far.

OPP reviewing allegations involving Di Ciano

But those inquiries are still at a preliminary stage and the force has not decided if there is a sufficient basis to launch a full, formal investigation, Staff Sgt. Carolle Dionne, an OPP spokesperson, said last week.

If cash did trade hands in exchange for a campaign donation, it could amount to a violation of the Municipal Elections Act, legal experts said.

Eric Gillespie, a Toronto-based municipal law expert, reviewed the audio tape.

"If the comments that we're hearing are being made by a campaign manager for a campaign that's active within the City of Toronto, to a donor — and that's certainly what it appears to be at the moment from these recordings — a) that doesn't look ethical, I think in the minds of many people, and b) that may well be illegal."

Politicians and their campaigns are not allowed to offer cash incentives to attract potential donors. Donors must use their own money to make campaign contributions.

Gillespie noted: "What appears to be happening here, some would say, is simply running it [the cash] through somebody else, filtering it through somebody else."

Large campaign deficit

CBC News contacted nearly a dozen donors who gave the maximum $750 to the 2014 Di Ciano campaign. Almost all of them said they gave willingly because they were family or friends of the Di Cianos. None of them said they were offered cash in exchange for their contributions.

Justin Di Ciano's campaign initially was in tough financial shape. At the close of the 2014 election period, he reported donations totalling only $10,950 against expenses of $65,240, and he and his spouse were personally on the hook for more than $28,000 of the difference, according to his filings.

He successfully applied to the city for a routine six-month extension of his fundraising period and, according to city records, collected a further $28,500 from donors through the first half of 2015. All those donations are listed as having been "accepted" in the final month of eligibility, June 2015, and all were for the $750 maximum.

If you have tips on this story contact John Lancaster at john.lancaster@cbc.ca or 416-205-7538