MONTGOMERY — Alabama Attorney General Steve Marshall took office Monday and immediately promised to step aside from any investigation by his staff of Gov. Robert Bentley, who appointed him.

Marshall, in remarks after his swearing-in ceremony, said he understood what he described as the "cloud" surrounding his appointment. There have been lingering questions about Bentley naming an attorney general at a time when there were hints the office might be investigating the governor.

Marshall said he did not know yet if there was an investigation of Bentley, but said ethical concerns will require him to step aside because someone could question his impartiality.

"If there is a direct of investigation of Robert Bentley I will personally recuse," Marshall said.

Marshall, who had been a Marshall County district attorney since 2001, said his priorities will include fighting public corruption, advocacy for crime victims and combating human trafficking.

"If you want to know what drives me. If you want to know what causes me to seek this job, it's that I have the opportunity to seek justice," Marshall said.

Marshall's appointment came a day after Bentley picked former Attorney General Luther Strange to take the U.S. Senate seat of Jeff Sessions, now the U.S. attorney general.

The questions about the appointments arose because Strange, in November, asked the House Judiciary Committee to pause an impeachment investigation of the governor, saying his office was doing "related work." He didn't elaborate on what it involved.

Marshall said he will meet with the special prosecution's division on Tuesday to see if there is an investigation of Bentley. If there is none, that should be explained. Marshall said he planned to meet with House Judiciary Committee chairman about the status of the impeachment probe.

Marshall said the potential investigation was not mentioned during his job interviews with Bentley.

"I would have walked away," he said if the governor brought up the subject.

Marshall was appointed Marshall County district attorney by then-Gov. Don Siegelman and won election three times. He is a graduate of the University of North Carolina at Chapel Hill and the University of Alabama School of Law.

During his career, he was involved in the passing of a law to track sales of ephedrine products to combat crystal meth production. He also led the first prosecution under "Brody's Law," which allows a person suspected of killing a pregnant woman to be charged with two murders if the fetus does not survive.

During Monday's ceremony, Marshall was praised by those who worked with him. Barry Matson, executive director of the Alabama District Attorneys Association, said Marshall was a hands-on prosecutor who took cases to the courtroom instead of just being an administrator.

"This is a man that exemplifies integrity," said state Sen. Clay Scofield said.