When is it illegal to offer a politician a job?

William Burck, a white-collar defense attorney at Weil, Gotschal & Manges and the former deputy White House counsel under Mr. Bush, said it did not matter that the position being discussed with Mr. Sestak was unpaid because a prestigious presidential appointment was itself a thing of value and the law made no distinction between paid and unpaid.

“The legal question comes down to the White House’s intent and Sestak’s understanding of what the White House wanted from him in return,” he said. “If the position was offered as a quid pro quo to induce Sestak not to run in the Democratic primary, then it could be viewed essentially as a bribe. If the job was offered to him without conditions, then it would be harder to prove any law was violated.”

Joseph Gibson, former chief counsel to House Judiciary Committee Republicans and author of “Persuading Congress,” dismissed the defense claiming that everyone does it.