The Democratic Party claims that, seven times in the past 42 days, its request to see his schedule has been either ignored or partially responded to, The (Columbus) Dispatch reported Tuesday.
"Serious questions remain regarding whether the governor has improperly used his office for the benefit of Mitt Romney, and it's deeply disappointing Kasich is so secretive he won't tell the public what he's done or where he's gone," Ohio Democratic Chairman Chris Redfern said in a statement.
The governor's office initially told the Democrats no records existed, then said the schedule could not be released because of security concerns. Some schedules were later provided but were incomplete, the newspaper said.
The suit will be filed in Franklin County Common Pleas Court, the statement said.