No idea what my kids’ school policy is. I have no idea why I as a parent would need to review one of their tests so it hasn’t been an issue.
If one of them had come home and told me that they felt a grade was unfair or there was an error, I’d view my job as helping them to navigate the process to discuss and resolve this issue themselves, not reviewing the actual test to insert my judgment on whether there was an error. There have been a few of those and we developed scenarios to practice what they could say and potential ways to resolve the problem.