South Australian Trade Minister David Ridgway says he won't stand aside after admitting to signing blank time sheets for his chauffeur before going overseas so he could get paid for driving other Liberal MPs.
Mr Ridgway said he signed the forms for Barry Jeisman on the way to the airport four years ago, and it had been a long-standing practice on both sides of politics to use the vehicle to represent their parties at events.
"I did so on the basis that he was driving the acting leader Michelle Lensink while I was away and she had a function to go to," the minister told reporters on Saturday.
The vehicle was always available for anyone who had a legitimate reason, he said.
"They needed to have the time sheets signed so my driver would get paid," Mr Ridgway said.
"This is a guy that had driven (former premier) Mike Rann for 22 years and me for three or four at the time.
"I thought it was a little unusual - I'd never done it before - but I was away for five weeks.
"There's certainly a level of trust there but I don't think that's an unreasonable thing to have.
"The gentleman was actually doing the work."
Mr Ridgway said the premier's office was "disappointed that it's been elevated to where it is" but a misconduct investigation into Mr Jeisman by Fleet SA had made no finding against the minister.
"At no time has there been any suggestion that I've done anything wrong."
Driver time sheets have since moved from paper to electronic records and Mr Ridgway said that's a change for the good.