Haneef's lawyer says inquiry is weak

The inquiry into Australian authorities' handling of the Mohamed Haneef case needs stronger powers to avoid becoming a "toothless tiger", the former terror suspect's lawyer says.

Solicitor Peter Russo said the upcoming inquiry, headed by former NSW Supreme Court judge John Clarke, needed "coercive powers" to force reluctant witnesses to testify.

He said the coercive powers would ensure all relevant documentary evidence is produced, and require relevant witnesses to attend and answer all questions which are properly within the terms of reference.

"Without such powers, the inquiry may very well be a toothless tiger," Mr Russo said in an article for a News Limited online weblog.

Mr Russo said it was not reasonable to assume those responsible for the errors in the handling of the case would voluntarily give away information which embarrasses themselves or their organisation.

"Without such powers, the people who should be answering the questions are well within their rights, if they choose, to take the standpoint taken by a petulant child who does not want to do something: You can't make me, so there," he said.

"It is reasonable to assume that where there has been government error, those in error are likely to be embarrassed, ashamed, some will be in self-protect mode and some will go to ground."

Dr Haneef was held for 12 days without charge in July last year following his arrest at Brisbane International Airport in connection with the botched UK terror plot.

He was then charged with supporting a terrorist organisation for giving away a SIM card to his cousin and terror suspect Dr Sabeel Ahmed, before the charges spectacularly collapsed later that month.

The Indian doctor was also subjected to an uphill battle to have his work visa reinstated after then immigration minister Kevin Andrews cancelled it on character grounds.

However, he is free to return to Australia, if he is able to find employment, after successfully appealing against the decision in the Federal Court.