He helped Ewen Macdonald get off a murder charge by not putting him on the witness stand, but top criminal defence lawyer Greg King can see an accused's right to silence one day coming to an end.

King was involved in a panel discussion at Victoria University's law faculty on Friday evening, discussing legal procedures with Sensible Sentencing Trust chairman Garth McVicar and Gil Elliott, the father of murdered Dunedin university student Sophie Elliott.

On the contentious issue of an accused's right to silence, King conceded the rules might one day change.

He defended Macdonald's not taking the stand in the recent high-profile Scott Guy murder trial, saying he had answered every question in a 40-hour police interview, giving the jury plenty of time to see his version of events.


But he said there was a contradiction in the system when people charged with fraud could have their right to silence removed.

"If your right to silence can be taken away from you because of benefit fraud, and you're being investigated in a murder charge ... why do you have it there?" King asked

He suggested one option in the future might be allowing the prosecution to apply to a judge for an order to make it compulsory for an offender to take the stand if it was considered vital enough.

McVicar said the right to silence created an "offender-friendly, criminal-centred legal process".

"I don't think Greg needed to rely on the right to silence in his last case [the Guy trial] - he'd already proven that a doubt existed."

But McVicar said New Zealand should follow the UK's lead in getting rid of the offender's right to silence.

"It appears our legal system is not about truth - if it was the right to silence would not exist,"said McVicar.

Elliott told the audience that King, who represented Clayton Weatherston - the man convicted of murdering his daughter - was the only person who talked to him and his wife, Lesley, through their trial.

"The prosecution ... just ignored us the whole time."