The assistant attorney heading up the prosecution of ex-Circuit Court Judge Herman Thomas abruptly resigned from the Mobile County District Attorney’s Office April 5 after the FBI executed a search warrant at his home.

Steve Giardini, who last week was assigned to help lead the prosecution of 57-count indictment against Thomas that was handed down by a special grand jury March 27, resigned his position as of Sunday afternoon, according to District Attorney John Tyson. Tyson could not elaborate upon why federal agents searched Giardini’s home or what they were looking for.

Giardini, 49, has worked in the DA’s office for more than 20 years and specialized in prosecuting sex crimes against minors. He has worked specifically with the Child Advocacy Center.

Tyson said he learned of the FBI search Saturday and had a conversation with Giardini’s attorney Dennis Knizley shortly afterward. He said that conversation continued Sunday.

“On the advice of his attorney, Giardini refused to answer my questions and resigned,” Tyson said.

Tyson had confirmed earlier in the day that Giardini was no longer employed with his office. As for how Giardini’s resignation would affect the Thomas prosecution, Tyson said the veteran prosecutor was never the only attorney leading the case and that he anticipates no interruption in the prosecution. As for naming a new lead prosecutor, Tyson said for “all intents and purposes, I’m the lead lawyer.”

Giardini’s expertise was to have been to ask sensitive questions of a sexual nature, Tyson said. He added that the turn of events has been shocking for his office.

“It is fair to say that everyone here and at the Child Advocacy Center and everyone interested in prosecuting crimes against children is in shock today,” Tyson said.

He stressed that the circumstances surrounding Giardini’s resignation have nothing to do with the Thomas case.