A federal government watchdog has discovered even more inside information leaked from the National Labor Relations Board to a former adviser to presidential hopeful Mitt Romney, according to a report released Wednesday.

The board's inspector general said NLRB member Terence Flynn committed serious ethical violations when he improperly shared early drafts of board decisions and details of internal deliberations with Peter Schaumber, who once advised Romney on labor issues.

A previous report from Inspector General David Berry in March had found other examples where Flynn revealed sensitive internal information from the board, which oversees union elections and labor-management disputes.

Berry said he expanded his investigation after Flynn publicly denied any wrongdoing.

"Mr. Flynn's public statement that he has engaged in no wrongdoing strikes at the very heart of the board and all but eviscerates the due process procedures that the Board has established," the report said.

Flynn is a Republican appointed to the five-member board along with two others by President Barack Obama in January. Berry said the ethical violations came in 2010 and 2011, when Flynn was a staff lawyer for the board.

The case has already been referred to the Justice Department for a separate investigation. It also has been forwared to the U.S. Office of Special Counsel to investigate potential violations of the Hatch Act, which prohibits federal employees from engaging in partisan political activity.

Flynn has denied any wrongdoing. In a statement Wednesday, his personal attorney, Barry Coburn, acknowledged that Flynn's actions did not reflect "perfect judgment in every instance." But he said they were not illegal and "there is not a shred of evidence that they were undertaken for any improper purpose."

Board chairman Mark Pearce said he takes the allegations very seriously and is considering how to respond.

"They raise questions of ethics and trust that go to the heart of the values shared by all of us at the NLRB," Pearce said.

Romney's campaign has said that Schaumber left his advisory post in December, around the time that the investigation into Flynn began.

In one instance, the inspector general's report found that Flynn secretly helped Schaumber draft an opinion column denouncing a board decision that favored unions. The report called Flynn's conduct "an abuse of his discretion."

California Rep. George Miller, top Democrat on the House Committee on Education and the Workforce, called on Flynn to resign his post. Sen, Tom Harkin, D-Iowa, chairman of the Senate Health, Education, Labor and Pensions Committee, also called for Flynn's resignation.

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