Democratic candidate for governor and state Sen. Vincent Sheheen has released a web-based advertisement criticizing Gov. Nikki Haley's continued support for the now-former DSS chief.

Embattled DSS Director Lillian Koller resigned on Monday, saying that her role as the agency's chief was "causing a distraction." DSS has been the subject of an ongoing investigation by a Senate panel after a few child welfare officials voiced concern over several deaths of children who had case files with the agency. As the investigation unfolded, several lawmakers called for Koller to resign or for Haley to fire her.

"Governor Haley chose Lillian Koller, defended her through months of reports proving mismanagement and suffering children, and continues to praise Koller following her resignation despite the major failings at DSS that allowed children to die and be kept in danger," said Andrew Whalen, Sheheen's campaign spokesman. "Leadership begins at the top, and clearly Nikki Haley can't be trusted to lead the government or demand accountability from her administration."

Following Koller's resignation on Monday, Haley said in a written statement that Koller put the well-being of South Carolina's children above her own. Haley added she will continue to be proud of Koller and the work she's done at DSS.

"Just more politics from trial lawyer Vince Sheheen," said Rob Godfrey, Haley's campaign spokesman, of the advertisement. "One has to wonder whether Vince was more concerned about children's welfare when he was defending drug dealers in court or when he was trying to get a child molestor's sentence reduced."

Republicans have criticized Sheheen for past work as a defense attorney, when he defended clients who had abused women. Sheheen, a Camden general practice attorney, has pointed to his work as a prosecutor and has said that he shouldn't be judged for his client's actions.