{mosads}Silver is now a senior fellow at the moderate think tank Third Way. He appeared before the committee on Tuesday to testify about his use of private emails while in office.

While at the Energy Department, he was at the center of the controversy surrounding the Obama administration’s decision to support the troubled solar energy company Solyndra. 

In response to the lobbyist’s email, which was released midway through the hearing, the heads of the committee threatened a legal response.

“I want an explanation from your counsel on why we shouldn’t refer this to the American Bar Association,” Rep. Darrell Issa (R-Calif.), the committee’s chairman, told Silver. “The question of whether we refer this to the Bar Association, whether in fact it’s an interference with Congress, which I find it to be, and the like, will need to be resolved with the ranking member and myself after this hearing.”

He added that the email “crosses the line.”

The top Democrat on the committee, Rep. Elijah Cummings (Md.), also seemed outraged.

“I hope this is not what it appears to be because I think it would be very unfortunate. It would be clearly out of bounds,” he said.

Silver could not explain the lobbyist’s email.