Trying to confront chase the perp was indeed a dumb idea. Though if you read the article they appear to have made multiple reports in the past. Thing is with police reports like this is by the time they arrive they only "see" vandalism which is all they can put in their report. Anything else you tell them is taken with a grain of salt, they arent psychics. In order for them to become actively involved they need to see the crime in progress or be presented with solid evidence. In the latter case you need to hire a private detective or DiY which is what they chose to do here.