Gwinnett County Sheriff Butch Conway said the FBI investigation that ensnared former Gwinnett Commissioner Shirley Lasseter on a bribery charge has the potential to bring down other local officials from as long ago as 2004.

In his first public comments on the Lasseter investigation, Conway said Wednesday that he has been hearing “very credible accusations” since 2004 involving payoffs to certain commissioners and their associates.

He said he first approached the IRS criminal investigations division seeking assistance with an investigation, but the IRS referred him to the FBI’s Public Corruption Task Force. Conway said he has had a deputy assigned to that group since 2010. .

Lasseter pleaded guilty in federal court last week to a bribery charge for taking $36,500 from an undercover FBI officer in exchange for her vote on a proposed real estate development in her Duluth district. Her son, John Fanning, and a Hall County businessman, Carl "Skip" Cain, also pleaded guilty to orchestrating the bribery scheme, and to federal drug charges. They will be sentenced Aug. 6.

Federal prosecutors said all three defendants are talking to authorities and could receive reduced sentences in exchange for their cooperation with the corruption investigation.

"Hopefully with the FBI looking into this, the county can move forward and get its reputation back," Conway said.

-- Staff writer David Wickert contributed to this story.