My opinion is that this was a big screw-up from the outset, and it was why the city of Louisville made a substantial settlement with the Taylor family.
As to whether it was criminal is a little less clear. At least one witness has said that the police announced themselves before entering. The police officers also claim they announced before entering. And even then, you can question whether that is smart police work or not. However, it is legal.
I apologize (profusely LOL), I meant to respond to another comment that referred to it that way.