Criminal Bar Association president Len Andersen said defence lawyers did not have the resources of the Crown and there was a real risk of a miscarriage of justice where, for example, potential eye witnesses were not interviewed as part of the initial investigation.
"Defence lawyers have expressed concern that the normal rule of investigation of offences does not seem to apply where allegations are of a sexual nature and, on the contrary, the complainant's accounts are not challenged and there seems to be a widespread assumption that such complainants are always telling the truth with little or no further investigation required," Andersen said.
"While it is appropriate that victims are properly supported, there can be no excuse for failing to carryout a proper investigation to determine whether there is substance to any allegation that may result in a prosecution. Sexual abuse allegations are easily made and the effects of an allegation are catastrophic on the person who is accused whatever the final verdict."
Andersen said it was clear the system did not work for the teacher charged who had to wait 12 months with charges hanging over his neck.
"The falsely charged teacher's year from hell is a normal experience that any person would face who was charged with a sexual offence. If he or she is successful in obtaining bail then the bail terms are likely to significantly affect his or her life and may even prevent employment," he said.
"Where there is a child making the allegation, child witness interviewers facilitate the giving of statements on video and it is not their role to challenge the child or his or her recollection.
"This emphasises the importance of the Police carrying out a proper investigation including a proper examination by the Police of the motives and accounts of complainants instead of uncritically accepting their word that a sexual assault has occurred where the assault is denied by the defendant."
After a six-day trial in the Auckland District Court the jury took less than an hour to return not guilty verdicts on all seven charges of indecent assault last month.
The teacher, who was cleared of indecently assaulting three schoolgirls, told the Herald he felt let down by the system as his life went into "total meltdown".
The teacher may never return to a classroom after his "year of hell".
"I don't think I could ever trust the system of education, BOT governance, school hierarchical support or the devious nature of some children to go back into a classroom," he said.
He cannot be named under law, but told the Herald that while the trial played out he had no faith in the outcome until he heard the last not guilty verdict read out in court.
