Criminal lawyers believe people with cognitive or mental difficulties are more vulnerable to the type of police investigation which has been implicated in a false confession.
Last month, Crown Law and police lost their legal fight to keep top-secret the technique - called the Complex Investigation Phased Engagement Model - used in the Lois Tolley murder case, which collapsed late last year.
The High Court Justice Simon France was scathing of the technique saying, "a man with an unusual and... confused way of thinking has been further confused by an unfair interview process".
The Criminal Bar Association's immediate past-President Len Andersen QC spoke to Māni Dunlop.
