DETROIT (WWJ/AP) – A plea appears to be in the works for a 74-year-old vendor charged in a bribery case involving a dozen Detroit school principals and one administrator.

A document filed Thursday in federal court in Detroit says a May 12 plea hearing is scheduled for Norman Shy of Franklin, owner of Allstate Sales, a DPS vendor of school supplies.

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According to court filings, a total of 13 DPS principals — including one who also worked as an administrator — allegedly conspired with Shy in a scheme to line their own pockets by submitting invoices for supplies that the schools were never to receive.  The scheme began in 2002 and continued until January 2015.

Court documents filed in U.S. District Court state:

Six former and current principals have been arraigned this week on conspiracy to commit bribery charges. Other arraignments are scheduled next week.

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The U.S. Attorney’s office says fraudulent invoices were submitted for supplies that were not delivered to schools or delivered in smaller quantities than ordered.

Authorities say Shy’s Allstate Sales received $2.7 million from the district. The principals and administrator received kickbacks of more than $900,000.

The Associated Press left an email Thursday evening seeking comment from Shy’s attorney.

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