But Le Clair asked Magistrate Robert Cook for an adjournment, saying he didn't have a lawyer, and needed more time to allow Legal Aid to process his application.

The case was stood down for little more than an hour.

It was during that short period that Mr Cook conducted an investigation that has been slammed as improper by ACT Supreme Court Justice John Burns.

Mr Cook asked someone, either a third party or Legal Aid itself, privately about the dealings between Legal Aid and Le Clair.

He came back to court and put it to Le Clair that he had been picky with the lawyers offered to him by Legal Aid.

Mr Cook alleged Le Clair had rejected the services of the lawyer who was offered to him, and was insisting on another.

Le Clair disputed that allegation, and the magistrate put no evidence of his assertion before the court, and did not reveal who had told him.

Despite that, he proceeded to reject Le Clair's application for an adjournment, forcing him to go to hearing without a lawyer and defend himself on the assault charge.

Le Clair was found guilty, convicted and sentenced for the crime.

He appealed against the decision not to give him the adjournment, this time represented by lawyer John O'Keefe, and the decision of Justice John Burns was published last week.

Justice Burns overturned Le Clair's conviction for assault and sent the matter back before the ACT Magistrates Court to be heard by another magistrate.

He strongly criticised Mr Cook's actions, describing the investigation as "grossly improper".

"The magistrate should not have conducted his own investigations," he wrote.

"He should have invited the appellant to provide evidence as to his dealings with the Legal Aid office, such evidence perhaps being constituted by evidence from the appellant himself together with evidence from an appropriate member of the Legal Aid office.

"At the very least, the appellant should have been given an opportunity to present evidence in relation to the question of his dealings with the Legal Aid office."

Mr O'Keefe, in a statement made after the judgment was handed down, said legal representation was an important right for defendants, something affirmed by Justice Burns' decision.

He said magistrates must have good grounds before forcing an accused to represent themselves at a hearing.

"Our adversarial system operates on the parties presenting evidence in court," he said.

"If a judicial officer makes his/her own inquiries, it undermines that system. In particular, the parties cannot test the accuracy of any information that has been gathered."

Justice Burns made it clear in his judgment, however, that magistrates were not required to grant an adjournment every time a defendant asks for one to get legal representation.

"Much will depend upon the circumstances of the case," he wrote.

"However, what I want to make clear is that, in exercising the discretion whether to grant an adjournment, a magistrate is expected to act judicially and to abide by the rules of natural justice and also procedural fairness."