Leaking documents to journalists is a common practice, a legal commentator has said in response to the controversy over the leaking to the media of a police interview transcript of Indian doctor Mohammed Haneef charged with providing reckless support in the failed UK terror plot.

Criminal barrister Greg Barnes said legal papers are commonly leaked to journalists.

"This happens on both sides, it's happening every day of the week in cases around Australia," Barnes told ABC radio.

"What needs to happen in Australia is the laws relating to lawyers speaking to the media need to be loosened," he said.

"We've actually got some proposals on the table at the moment which would further restrict the way in which lawyers can talk about their client's cases and I think that would be a big mistake." Barnes said.

Haneef's barrister in his criminal trial, Stephen Keim, yesterday admitted leaking a police interview with Indian doctor Haneef.

Keim denied any wrongdoing and challenged authorities to present legal advice that would suggest the leak was a breach of the law.

"You've got leaks coming from police officers, from the same document, and the prime minister doesn't complain about that," Keim said, adding, "They're obviously designed to suggest that the Commonwealth case against my client is stronger than it appears from the evidence."

An Australian judge has questioned the Immigration Department's interpretation of the character test used to revoke the visa of Haneef, saying that even he would fail the test considering his association with people suspected of criminal conduct.

Justice Jeffrey Spender described it as astounding the Australian government's position that an association of any kind with criminals -- "A cup of coffee, a picnic with the kids" -- is enough for a non-citizen to fail the Migration Act's character test.

Justice Spender said that he too would fail the test according to the government's interpretation, which was explained at a hearing into whether the Immigration Minister, Kevin Andrews, acted lawfully when he cancelled the working visa of the Gold Coast doctor on Monday, The Age said.

"I have been associated with persons involved in criminal activity. I have defended them, charged with murder. Unfortunately I wouldn't pass the character test on your statement," the judge told Roger Derrington, SC, representing the minister.

"You're not a non-citizen," was the government barrister's reply. "The purpose of the migration legislation is to protect the national interest, the Commonwealth doesn't have the power to investigate the relationships of people overseas."

Justice Spender's voice rose. "That's absolutely astounding, Derrington."

The complex arguments about the legal meaning of "association" and over who should have access to the protected information will have to wait until August 4, when a full hearing will be held.

Haneef on filed an appeal in a federal court against Australian government's decision to cancel his visa and keep him behind bars.