SA judge 'asked too many questions'

A South Australian man has had his sex convictions overturned after the judge at his trial intervened too often and asked too many questions.

The man, who cannot be identified, was convicted on two counts of indecent assault and one count of rape related to a girl who was aged between 13 and 16 at the time.

But the South Australian Court of Criminal Appeal has set aside the convictions and ordered a new trial, ruling that the defendant was not afforded a fair trial in the District Court after a judge intervened 180 times and asked 438 questions.

The court said the judge had assumed the mantle of advocate and his questioning went beyond clearing up ambiguities or assisting the jury to better understand the evidence.

"On occasions the judge's questions suggested incredulity on his part," the judgment just published said.

"On other occasions he took over the role of the prosecutor."

The appeal court said it did not matter how strong the crown case against the defendant was because the entering of the judge into the "arena of counsel" was so numerous and so extensive it could not be said that the trial was fair.