Documents filed as part of an attempt to pause the investigation into irregular contributions to Jeff Callaway's United Conservative Party leadership campaign shed light on a potentially illegal corporate donation and show the commissioner has ordered Callaway to repay $26,500.

On March 11, Alberta Election Commissioner Lorne Gibson ordered Callaway to repay the contributions to his campaign and to account for where it came from, how and when it was donated and how the funds were received by the campaign.

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Both Callaway and his chief financial officer, Lenore Eaton, are addressed in the letter. It is not known if Callaway has returned the funds.

It's just one of the documents revealed as part of a package submitted by Callaway and five others as part of an effort to put commissioner Gibson's investigation on hold until after the election.

That effort failed, but it did expose the previously secret documents to public scrutiny. Previous documents obtained by CBC News came through leaks from sources.

New information on donations

As previously reported by CBC News, one document in the injunction file shows Eaton faces up to two years in prison or a fine of $50,000 for alleged "corrupt practice" in breach of the Elections Act.

A recently uncovered document shows Calgary businessman Robyn Lore could face the same penalty.

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In the letter addressed to Lore — one of the plaintiffs attempting to stall the investigation — the commissioner says there is reason to believe a corporation controlled by Lore donated $60,000 to the Callaway campaign through its communications manager, Cam Davies.

The commissioner says the full amount was deposited in Davies' personal account on Sept. 11, 2017, and then "all or significant portions" were "directed to the Jeff Callaway campaign in a manner that has been determined to be in contravention of the [Election Finances and Contributions Disclosure Act]."

Corporations are barred from making political donations.

Money that is not their own

So far, three people have been fined for donating money to the Callaway campaign that was not their own, while two others have received letters of reprimand for the same offence.

Happy Mann was one of those fined for making irregular donations. He told CBC News that he agreed to have his name and the names of two others attached to donation forms pre-filled in the amount of $3,000 each.

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He said money was then attached to those donations but that he wasn't aware where the money came from and that none of it passed through his accounts.

That assertion was corroborated by the findings of the election commissioner.

Concerns over obstruction

Several letters from the commissioner show concern that someone is interfering in the investigation and trying to convince people not to co-operate.

It's also clear the commissioner has been having a hard time nailing down interviews with some people involved in the investigation. Both Nicole Callaway and Robyn Lore previously indicated they would not show up for their scheduled interviews.

"Summons were only issued to some applicants after weeks of trying to contact them, with no reply or cancelled interviews, partial or no provision of requested documentation, missed deadlines and adjournment requests being granted," reads one letter.

Davies was fined a total of $15,000 in February for obstruction of an investigation.

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It's alleged Callaway ran a "kamikaze" campaign on behalf of current UCP Leader Jason Kenney, with the sole purpose of attacking Kenney's chief rival, Brian Jean.

Both Kenney and Callaway deny the allegations, but documents obtained by CBC News show deep co-operation between the two campaigns, with high-ranking Kenney officials providing resources, including strategic political direction, media and debate talking points, speeches, videos and attack advertisements.

Among those officials was Kenney's current deputy chief of staff, Matt Wolf.