Nobody knows the limit of their tools until those limits are known. Where did you decide they thought they were infallible? They followed the law they have, as is their job. Justice is not perfect, we don't have all the answers, jumping to such vicious conclusions speaks more about you than them. The entire incident, and her successful appeal after further investigation, was like a year. Nobody threw the woman into prison for a decade or something. Seriously, people are so reactionary.

If the state has good reason to believe someone had abducted children, I would want them to intervene, would you not?