By Jack Fink

DALLAS (CBSDFW.COM) – In a unanimous vote Wednesday, Oct. 27, the Dallas City Council approved hiring the Kirkland and Ellis law firm to get to the bottom of the city’s data loss earlier this year.

The investigation will be conducted by a four-person team headed by the previous U.S. Attorney for most of North Texas, Erin Nealy Cox.

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The contract will cost nearly $550,000.

Council Member Cara Mendelsohn said, “This is important. All of us have to care about this. This is critical to our city.”

Council Member Paula Blackmon agreed. “We need to regain trust and confidence in our public.”

The city issued its own 131-page report last month and found the IT department lost about 21 terabytes of data and more than eight million files, including archived videos, audio, and case notes from the Dallas Police Department.

Nearly 17,500 cases could be impacted the city said, including one thousand prioritized by the Dallas County District Attorney’s Office.

CBS 11 reached out to the DA’s Office Wednesday seeking comment, but didn’t hear back.

City administrators hid the data loss from the public and most city council members for four months.

The city went public after District Attorney John Creuzot called officials about it.

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Assistant Dallas County Public Defender Brad Lollar, who represents 11 defendants charged with murder, praised the independent investigation. “I think it’s a good thing, because I don’t think anybody necessarily trusted what the IT department at the city of Dallas said it would do or has done. We were all distressed to hear about the massive loss of data to begin with.”

For now, the city says DPD and prosecutors continue reviewing their files to see if any evidence has been lost.

The council’s decision comes as the Dallas FBI continues its own investigation into whether the data loss was intentional.

The FBI probe could delay the start of the law firm’s investigation, which would take about 90 days to complete.

In its report, the city found, “City personnel failed to faithfully follow the data migration procedures provided by the software vendor” and found there is a “lack of understanding among the IT staff and leadership as to the importance of data management controls, policies, standards, and procedures.”

The city’s Chief Information Officer, Bill Zielinski, was asked about this during a council committee briefing earlier this month.

“There are instances where we are lacking the basic underlying policies altogether. In those instances, I can’t really hold staff to account for something that is not appropriately or properly documented.”

The city has said the employee who deleted the data had done this twice before and was fired.

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Zielinski said employees may face disciplinary action.