Auditors got suspicious when invoices showed a mental-health professional working with Indigenous patients had billed Health Canada for more than 28.5 hours of counselling in a single 24-hour period.

After painstaking analysis of hundreds of invoices, Health Canada abruptly terminated its agreement with the woman late last year when auditors reported she had overbilled taxpayers for up to $360,255.

CBC News uncovered the latest case of overbilling in Health Canada's programs for First Nations and Inuit people through documents obtained through the Access to Information Act.

A woman and a young boy walk through the northern Ontario First Nations reserve in Attawapiskat. Health Canada is responsible for providing health care to First Nations and Inuit members, who are not covered under provincial or territorial plans, but has identified $12 million in overbilling since 2009. (Nathan Denette/The Canadian Press)

The overpayment amount was buried in an obscure section of the Public Accounts of Canada, tabled in Parliament last month, without detail or explanation.

But a heavily censored 46-page audit report, dated May 31, 2016, shows the woman was paid to counsel residential-school survivors and others in the Ontario region. The report says it's unlikely she actually provided all the services claimed for all her patients.

Health Canada spokeswoman Maryse Durette declined to provide details of the case, including the identity of the woman, "because the investigation is still ongoing." Durette would not say whether police were alerted, charges laid or lawsuits filed.

Ninth case

The Public Accounts of Canada say only that Health Canada expects to recover the $360,255 in "subsequent years."

It's the ninth case since 2009 involving Health Canada overpayments for health services allegedly provided to First Nations and Inuit patients, who are not covered under provincial or territorial health plans.

The latest overbilling brings the total overpayments reported to Parliament to more than $12 million in the last seven years, though some of that money has since been adjusted or recovered.

The audit report contains a series of six recommendations, all of them blacked out under provisions of the Access to Information Act that protect personal information, solicitor-client privilege and advice to senior officials.

The document does indicate, however, that Health Canada has weak controls and oversight, something the department had been warned about previously.

Many validity concerns were identified including daily billings beyond 24 hours, which was considered impossible ... - Internal Health Canada report on overbilling by Ontario therapist

The programs "have an unduly elevated risk of intentional or unintentional manipulation of their terms and conditions as a result of shortcomings in their respective internal controls," the auditors found.

The department was alerted to the potential overbillings by someone outside Health Canada, who complained that the woman had asked people "to sign attendance sheets for … counselling sessions that had not occurred."

Auditors then drilled down into the dense paperwork, key parts of which were missing because a Jan. 25, 2013, flood ruined many of the files, which were then discarded, the woman said.

"Many validity concerns were identified including daily billings beyond 24 hours, which was considered impossible, and daily billings for 19.5 to 24 hours, [which] was considered almost impossible."

In the end, the auditors could only surmise the amount of overbilling because of the incomplete records.

'Legal action if required'

Between 1998 and 2015, they determined, the woman had billed Health Canada $2.1 million, with the overbilled amount likely between $121,620 and $360,255 — the latter number the only one reported to Parliament. If the latter number is correct, it represents about 17 per cent of total billings.

Durette of Health Canada notes the department has nearly 25,000 service providers, and operates a rigorous audit program to catch overbilling and fraud.

The department "initiates actions to recover these funds through claim reversal and other methods, including legal action if required," she said. "Between 1999 and 2016, more than $24 million was recovered."

Health Canada claims former UBC dentistry associate dean defrauded a program intended to provide dental services to First Nations patients. (UBC)

One high-profile alleged fraud in Health Canada's programs for First Nations and Inuit involves Dr. Christopher Zed, a former dentist at the University of British Columbia, who provided dentistry services in Haida Gwaii. Zed resigned from the university's school of dentistry in 2013 after working there nearly 20 years.

The federal government has filed a suit against Zed and the university, saying only $7.3 million of the $10.6 million provided for clinics was actually spent on the services.

Zed, who is also being sued by the Skidegate Indian Band, has not responded to the government's claim. In the Skidegate suit, Zed has said he was not unjustly enriched.

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