I know exactly what you are talking about. When I taught school there were so many parents who came to the rescue of their misbehaved kids. It was awful. No matter what the child did or how wrong the behavior was, they made an excuse and turned the situation around where it was your fault and not theirs. After seeing this so often the only satisfaction I had was to imagine this child as a teenager and adult and then ask the parent if it was the right thing to do at the time. They the parents will pay in the long run. Their kids will always be in trouble and then they will be sorry. Too bad society will also pay to have them around. Poor kids will never learn responsibility and independence. Pity!!
And of course, the parents will be saying "where did we go wrong?????" Duhhhhh!