Detroit — An investigation into alleged corruption in the Detroit police narcotics unit has identified possible false affidavits that led to convictions which may be overturned, a police official said Thursday.

Christopher Graveline, director of the Detroit Police Professional Standards Section, told the Board of Police Commissioners the six-month investigation has uncovered "about a half-dozen possibly false affidavits," and he suggested there could be more.

"We're identifying as many false affidavits as possible," Graveline said after board chair Lisa Carter asked for an update on the investigation. "We're working on about a half-dozen cases that might lead directly to (people) whose convictions might be expunged, or might be let out of jail."

Files from the extensive investigation are so numerous, officials had to use space at the Detroit Police Academy to house them, Graveline said.

Detroit police internal affairs officers raided the department's Major Violators Section, formerly the Narcotics Section, on Aug. 22, seizing dozens of files and 50 computers.

A team of 17 investigators made up of Detroit police officers, FBI agents and Michigan State Police troopers uncovered alleged corruption that includes drug cops planting evidence, lying to prosecutors in search warrant affidavits, robbing dope dealers and embezzling funds, police officials said.

Chief James Craig said Thursday the inquiry is progressing, and that he expects to give an update "in a few weeks."

"I’m comfortable with the speed at which we're moving forward in this complex investigation," he said. "We appreciate the collaborative effort with the other agencies, and now, eight months in, we believe we'll soon have additional information to tell the public about the progress we're making."

The investigation is looking at 10 years of activity by drug cops. Graveline said if problems are found with cases earlier than that, those would be investigated as well.

After launching the probe, Graveline set up a hotline urging anyone with knowledge of misconduct by drug officers to call (313) 596-3190. Since then, police have investigated more than 60 tips from the hotline, he said.

Graveline told the board the investigators are digitizing paper records, which he said are extensive.

"We conduct between 700 and 1,000 drug raids every year, so you're talking 7,000 to 10,000 records," Graveline said. "We couldn't find a room big enough for all those files; we had to put them in the Detroit Police Academy."

Some civil rights groups have criticized the police department heading the investigation into its own unit, calling for an outside agency to conduct the probe. Police Commissioner Willie Bell echoed that criticism at previous board meetings, but on Thursday he said he changed his mind after meeting with Craig.

"We had an in-depth discussion with Chief Craig, and I have full confidence in DPD to do a thorough investigation," Bell said. "I retreat from my statement about a month ago; after the briefing, I'm confident this will be done right."

Craig said he wanted outside agencies brought in, but insisted Detroit investigators needed to be involved in the probe because there are possible departmental violations that wouldn't be in the purview of outside agencies.

Graveline said the other agencies are intimately involved in the investigation.

"I think what you’ll see in the final product is that we’re working every day with the FBI; they’re with us on a daily basis conducting interviews. Also, we've had multiple discussions with the U.S. Attorney's Office and Wayne County Prosecutor's Office. They're going to be the decision-makers, so we're working collaboratively with them."

ghunter@detroitnews.com

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