A Charles Sturt University (CSU) academic says alleged misuse of parliamentary travel entitlements by Ministers needs prompt and decisive action by the Prime Minister.

Associate Professor of political science in the CSU School of Humanities and Social Sciences, Dominic O'Sullivan (pictured), says that the Prime Minister Mr Malcolm Turnbull has made a serious political miscalculation in allowing the Minister of Health, Sussan Ley, to 'stand aside' while her claims for repeated travel to the Gold Coast are investigated by the head of his department.

"The Prime Minister is correct in natural justice, but it should not take long to establish whether or not the rules have been breached," Professor O'Sullivan said.

"The Minister should be dismissed immediately if she has erred, or be robustly defended by the Prime Minister and allowed to stay if she has not.

"The Prime Minister's 'middle ground' position means that whatever the true story, it will remain a distraction for the government which desperately needs to regain control of the political agenda," Professor O'Sullivan said.

Ms Ley has insisted she has not broken any rules and plans to return to the ministry when the investigation is complete.

Senator Nick Xenophon and the Independent Member for Denison, Mr Andrew Wilkie, have both proposed reforms to parliamentary entitlements. Neither proposal has been acceptable to the Coalition or the ALP.

"Nor has the review been fully considered that was instigated by the former Prime Minister Tony Abbott following the private use of a taxpayer-funded helicopter journey by the former Speaker of the House of Representatives, Bronwyn Bishop," Professor O'Sullivan said.

"Now, however, the Sussan Ley case gives the Prime Minister the opportunity to act decisively, to present himself as attentive to public sentiment and responsive to the public interest.

"On the other hand, parliamentary democracy is expensive," Professor O'Sullivan said.

"Ministers need to be accessible to the public and need to be available to interest groups in their portfolio areas all over the country. If there is any limit on members and senators being accessible to the public, at public expense, parliamentary democracy itself becomes ineffective."