The federal opposition is calling for an independent investigation into claims the navy abused asylum seekers, saying it's the only way to vindicate the Australian personnel.
Speaking to Sky News, Mr Thistlethwaite said the claims should be heard with scepticism but investigated.
"We are dealing with people that are in desperate situations, and we should bring a healthy scepticism to claims such as this," he said, "but the appropriate course is to have them independently investigated, that's the best way to vindicate the navy."
The ABC has admitted it should been "more precise" when reporting allegations that asylum seekers were forced by the navy to hold on to hot engine parts.
The coverage sparked a backlash against the public broadcaster, but the abuse claims have been given fresh impetus after being reported again in Fairfax Media.
The government has rejected the claims, and Defence Minister David Johnston has pushed for an inquiry into the ABC for "besmirching" the navy's reputation.
Finance Minister Mathias Cormann said the allegations were made by someone who had "an interest in creating certain perceptions".
"There is absolutely no suggestion that there is any truth in these allegations whatsoever and we reject them out of hand," he told Sky News on Saturday.
