The gambling investigation caused less concern in the governor’s office because officials there considered it without merit, Mr. Ehrlich said. But because of lingering suspicions in Maryland political circles that Mr. Ehrlich’s people had a hand in Mr. DiBiagio’s departure in early 2005, a longtime aide to the governor, Jervis Finney, called Mr. DiBiagio a few months ago to deny any involvement, Mr. Finney said.

Image Thomas M. DiBiagio, former United States attorney for Maryland, in 2002. Credit... Gail Burton/Associated Press

Mr. Finney said in an interview Monday that he wanted to “clean things up” and to let Mr. DiBiagio know that “neither Gov. Bob Ehrlich or his representatives had asked the Department of Justice to push him out.”

Mr. DiBiagio said he did not accept the explanation.

“I believe it was that investigation that played an integral role in what was done to me,” Mr. DiBiagio, now at a law firm here, said about the gambling inquiries. “I clearly got the message that I had alienated my political sponsor and I would not have any political support to stay another term. Clearly, they wanted me to leave.”

Mr. DiBiagio pointed to tense conversations in 2003 and 2004 with advisers to the governor who, he said, intimated that the corruption investigations could derail his career. He would not name them publicly.

The former prosecutor said he was particularly troubled by one visit in June 2004 in which, he said, a lawyer allied with the governor said the gambling inquiries were disrupting legislative consideration of the slots question and should be shut down.

Mr. DiBiagio said the lawyer inquired about his political future, asked whether he was interested in being a judge and suggested that his life could be closely scrutinized.

Mr. DiBiagio said he described the conversation in a memorandum for his records and reported it to an official of the Federal Bureau of Investigation in Baltimore as a possible threat.