I would like to suggest under the certifying instructors that all instructors expected to teach children should be required to have a criminal background check specifically looking for any sex crimes history. Also be aware that there are different levels of background checks that can been done. The results of the background checks should be on file at the dojo.
Also, there needs to be a section of how to handle reports of possible inappropriate activity in the dojo. First, they should not be ignored or blown off as someone being dramatic. Second, the school should do its own investigation. Third, if that investigation is not possible report to a higher authority. Fourth, report it to the the police.
These are just things I'm pulling from the top of my head. I'll try and pull some references from the internet.