MINNEAPOLIS (WCCO) — The Minnesota Department of Human Services is investigating expense accounts of a federal court monitor who billed Minnesota taxpayers more than a $1 million for his work.

Auditors are checking whether the Pennsylvania-based consultant improperly charged the state for items as small as out-of-state tolls and as large as first-class plane tickets.

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Federal Judge Donovan Frank appointed Court Monitor David Ferleger to make sure Minnesota follows orders to fix serious abuses of disabled patients.

And he acts as a court-appointed consultant, making sure the state keeps a promise to reform Minnesota’s sex offender treatment program.

Ferleger is a nationally-recognized legal expert in civil rights and health care. But the Minnesota Department of Human Services — which pays all of Ferleger’s expenses — is alarmed at his spending habits.

DHS Commissioner Lucinda Jesson told Ferleger in a letter from April 7 that she is “concerned” about his spending habits after discovering three first-class airplane tickets charged to the state in January.

“In the upcoming days, our internal audits office, at my request, will review the past billing practices … to ensure appropriate internal controls and proper use of taxpayer dollars,” Jesson wrote.

Ferleger and his staff charged taxpayers almost $1.3 million ($1,262,746.66) since 2012, including 13 first-class airline tickets — some as high as $1,800 round trip from Philadelphia. Minnesota requires the use of the lowest round-trip airfare.

He bills $120 an hour for an assistant, which is twice the rate of the highest-paid DHS attorney.

And he bills nearly double Minnesota’s meal reimbursement, using the federal government’s $71 a day instead of the state’s $36.

Ferleger declined to comment on our story, telling WCCO, “I am a member of the court’s staff, and … do not give interviews.”

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But in a written response to lawyers in the case, he denied charging the state for first-class tickets. He said he paid for upgrades himself.

“I have no practice of buying first class airfare,” Ferleger wrote. “This is true for myself, staff and consultants. DHS has never filed an objection to any airfare or any other expense. My seating is often upgraded at no cost to the litigation; therefore, a receipt may show seating in first class. Per diem expenses are reimbursed at the total level for federal court jurors; additional actual per diem expense is not billed at all.”

Ferleger also said he’s unaware of any problems with DHS.

“I am aware of no current disagreement with DHS regarding any fees or expenses,” Ferleger wrote. “The several questions raised within the last few weeks were all resolved amicably, with no objections filed by DHS to anything.”

However, the DHS says the audit of Ferleger’s expenses is continuing.

Meanwhile, the State of Minnesota admits it never formally objected to Ferleger’s expenses until it saw the latest round of first-class tickets.

In her letter to Ferleger, DHS Commissioner Jesson calls that oversight, “a disservice to Minnesota taxpayers and the Court.”

Jesson now says her office will personally review all future receipts. She declined our multiple requests for comment on this story.

Judge Donovan Frank also declined comment, citing “pending litigation.”

Click here to read Jesson’s letter to Ferleger regarding his expenses.

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Read Ferleger’s response (Page 1, Page 2, Page 3).