The former chief information officer at Mayer, Brown LLP appeared in federal court today to face accusations that he set up a scheme to fraudulently obtain hundreds of thousands of dollars of the firm's money.

The U.S. attorney's office accused David Tresch, 51, of approving invoices to pay an information technology vendor that got nearly all of its income from the firm. The vendor, the criminal complaint says, then paid Tresch.

Tresch joined Mayer, Brown — which isn't named in the complaint — in 2004 as server operations manager. The firm promoted him to director of global operations in 2008 and chief information officer in 2011.

In February 2011, the firm told Tresch to stop using the vendor, which the complaint only identifies as a Schaumburg company.

But the vendor submitted invoices to the firm between April 21, 2011, and May 2, 2012.

Tresch approved those invoices — totaling $980,000 — that the vendor submitted for work it didn't actually perform, the complaint says. From May 2011 through last May, the vendor wrote 11 checks totaling $854,250 to Tresch, the U.S. attorney's office alleges.

In addition, Tresch maintained a financial relationship with the vendor that started in 2005, the complaint says.

Mayer, Brown told federal authorities that Tresch never disclosed his relationship with the vendor, which paid Tresch and his wife about $1.3 million between February 2005 and March 2011.

The firm paid $7.8 million to the vendor between November 2004 and March 2011, the complaint says. The U.S. attorney's office alleges that the figure represents about 95 percent of the vendor's total income in those years.

The firm fired Tresch on June 28 and contacted federal authorities.

Mayer, Brown issued a statement today that says, in part, that it will continue to cooperate with the U.S. attorney's office "but will have no further comment at this time in deference to the ongoing criminal investigation."

U.S. District Magistrate Judge Sidney I. Schenkier agreed today to release Tresch on a $100,000 partially secured bond after Tresch posted a $45,000 cashier's check. The FBI also seized Tresch's bank accounts with about $210,000 in deposits, a camping trailer, a van, a mobile home and a 2011 Cadillac DTS.

Tresch surrendered his passport and, as of today, faces one count of mail fraud.

Assistant U.S. Attorney Terra L. Reynolds appeared in court for the government. A spokesman for her office said the investigation continues.

Kent R. Carlson of Kent R. Carlson & Associates P.C. represents Tresch. Reached outside of the courtroom, Carlson declined to comment.

Tresch returns to court on Wednesday to tell Schenkier whether he wants a preliminary hearing.