The police didn't act in a crazy fashion at all. They responded to a complaint, collected evidence, checked it against vehicle owner records. Then they visited the owner of the vehicle, gathered some more information. When an arrest warrant was issued (by the court, not by the police) months later, the police telephoned the author of the article to advise her about it and make arrangements for her to come to court.

I've said repeatedly that I don't think there was any point in bringing a prosecution. since you don't live in the US maybe you don't appreciate that the police and the public prosecutor are completely separate entities. The police didn't do anything abnormal in this case.