The move comes two months after The Associated Press reported Bennett kept multiple campaign databases on Department of Education servers and ordered his staff to dissect a speech by his Democratic opponent for inaccuracies last fall. Bennett's computer calendar also included more than 100 entries labeled "campaign calls" between July 2011 and November 2012.
Bennett released a statement Thursday saying he looks forward to working with the commission and Thomas' office "to demonstrate proper adherence to state rules and guidelines."
"Throughout my time in public service I made every effort to be cognizant of and to follow state rules and guidelines for elected officials," Bennett said.
Indiana law prohibits state employees from engaging in political activity, including seeking contributions, while on duty or acting in an official capacity. It also bars state employees from working on anything outside their official job duties while on the clock, or ordering others to do so, and from using state resources for political purposes.
Violating the official duties law, known as the "ghost employment" statute, is a felony punishable by up to three years in prison.
State Senate Minority Leader Tim Lanane, who called for an investigation of Bennett's actions in September, welcomed Thomas' complaint.
"The commission needs to find out exactly what happened, what the facts are," the Anderson Democrat said in a telephone interview.
Indiana Democratic Party Chairman John Zody issued a statement saying Bennett, a Republican, "led a culture of corruption by misleading Hoosiers and abusing the trust of the office to which he was elected."
Bennett was a national star in conservative education circles until his abrupt resignation as Florida's education commissioner Aug. 1. His decision to step down followed outcry over an AP story showing he oversaw changes to Indiana's school accountability system in 2010 after learning that a school founded by a prominent GOP donor — and which he had consistently hailed as a top performer — had scored a C.
Bennett has previously denied instructing his staff to do campaign work and told the AP in September that one of the lists was used to make "thank you calls" on his own time after the 2012 election.
Bennett has said all the campaign calls were made on his own time and outside his office.
The campaign documents were found on Department of Education computers after Bennett lost the election to Democrat Glenda Ritz. They include an Aug. 28, 2012, email that Bennett sent to chief of staff Heather Neal and other aides from his state account directing them to review a campaign speech by Ritz.
"Below is a link to Glenda's forum in Bloomington. It is 1:35 minutes. I would ask that people watch this and scrub it for every inaccuracy and utterance of stupidity that comes out of her mouth," Bennett wrote in the email obtained by The Associated Press.
Three fundraising lists and a donor call list tailored for Bennett also were discovered on the computers. They include an expansive database of more than 6,500 party activists and volunteers created in 2009 by his then-communications director, Cam Savage. That list includes a footnote that it is licensed by Salesforce.com, the party's fundraising tool, to the Indiana Republican State Committee.
Savage didn't immediately return calls seeking comment Thursday.